testing.adoc

[[testing]]
= Testing
:doc-root: https://docs.spring.io
:api-spring-framework: {doc-root}/spring-framework/docs/{spring-version}/javadoc-api/org/springframework
:doc-spring-boot: {doc-root}/spring-boot/docs/current/reference
:toc: left
:toclevels: 4
:tabsize: 4
:docinfo1:

This chapter covers Spring's support for integration testing and best practices for unit
testing. The Spring team advocates test-driven development (TDD). The Spring team has
found that the correct use of inversion of control (IoC) certainly does make both unit
and integration testing easier (in that the presence of setter methods and appropriate
constructors on classes makes them easier to wire together in a test without having to
set up service locator registries and similar structures).




[[testing-introduction]]
== Introduction to Spring Testing

Testing is an integral part of enterprise software development. This chapter focuses on
the value added by the IoC principle to <<unit-testing, unit testing>> and on the benefits
of the Spring Framework's support for <<integration-testing, integration testing>>. (A
thorough treatment of testing in the enterprise is beyond the scope of this reference
manual.)




[[unit-testing]]
== Unit Testing

Dependency injection should make your code less dependent on the container than it would
be with traditional Java EE development. The POJOs that make up your application should
be testable in JUnit or TestNG tests, with objects instantiated by using the `new`
operator, without Spring or any other container. You can use <<mock-objects, mock objects>>
(in conjunction with other valuable testing techniques) to test your code in isolation.
If you follow the architecture recommendations for Spring, the resulting clean layering
and componentization of your codebase facilitate easier unit testing. For example,
you can test service layer objects by stubbing or mocking DAO or repository interfaces,
without needing to access persistent data while running unit tests.

True unit tests typically run extremely quickly, as there is no runtime infrastructure to
set up. Emphasizing true unit tests as part of your development methodology can boost
your productivity. You may not need this section of the testing chapter to help you write
effective unit tests for your IoC-based applications. For certain unit testing scenarios,
however, the Spring Framework provides mock objects and testing support classes, which
are described in this chapter.



[[mock-objects]]
=== Mock Objects

Spring includes a number of packages dedicated to mocking:

* <<mock-objects-env>>
* <<mock-objects-jndi>>
* <<mock-objects-servlet>>
* <<mock-objects-web-reactive>>


[[mock-objects-env]]
==== Environment

The `org.springframework.mock.env` package contains mock implementations of the
`Environment` and `PropertySource` abstractions (see
<<core.adoc#beans-definition-profiles, Bean Definition Profiles>>
and <<core.adoc#beans-property-source-abstraction, `PropertySource` Abstraction>>).
`MockEnvironment` and `MockPropertySource` are useful for developing
out-of-container tests for code that depends on environment-specific properties.


[[mock-objects-jndi]]
==== JNDI

The `org.springframework.mock.jndi` package contains a partial implementation of the JNDI
SPI, which you can use to set up a simple JNDI environment for test suites or stand-alone
applications. If, for example, JDBC `DataSource` instances get bound to the same JNDI
names in test code as they do in a Java EE container, you can reuse both application code
and configuration in testing scenarios without modification.

WARNING: The mock JNDI support in the `org.springframework.mock.jndi` package is
officially deprecated as of Spring Framework 5.2 in favor of complete solutions from third
parties such as https://github.com/h-thurow/Simple-JNDI[Simple-JNDI].


[[mock-objects-servlet]]
==== Servlet API

The `org.springframework.mock.web` package contains a comprehensive set of Servlet API
mock objects that are useful for testing web contexts, controllers, and filters. These
mock objects are targeted at usage with Spring's Web MVC framework and are generally more
convenient to use than dynamic mock objects (such as http://easymock.org/[EasyMock])
or alternative Servlet API mock objects (such as http://www.mockobjects.com[MockObjects]).

TIP: Since Spring Framework 5.0, the mock objects in `org.springframework.mock.web` are
based on the Servlet 4.0 API.

The Spring MVC Test framework builds on the mock Servlet API objects to provide an
integration testing framework for Spring MVC. See <<spring-mvc-test-framework>>.


[[mock-objects-web-reactive]]
==== Spring Web Reactive

The `org.springframework.mock.http.server.reactive` package contains mock implementations
of `ServerHttpRequest` and `ServerHttpResponse` for use in WebFlux applications. The
`org.springframework.mock.web.server` package contains a mock `ServerWebExchange` that
depends on those mock request and response objects.

Both `MockServerHttpRequest` and `MockServerHttpResponse` extend from the same abstract
base classes as server-specific implementations and share behavior with them. For
example, a mock request is immutable once created, but you can use the `mutate()` method
from `ServerHttpRequest` to create a modified instance.

In order for the mock response to properly implement the write contract and return a
write completion handle (that is, `Mono<Void>`), it by default uses a `Flux` with
`cache().then()`, which buffers the data and makes it available for assertions in tests.
Applications can set a custom write function (for example, to test an infinite stream).

The <<webtestclient>> builds on the mock request and response to provide support for
testing WebFlux applications without an HTTP server. The client can also be used for
end-to-end tests with a running server.



[[unit-testing-support-classes]]
=== Unit Testing Support Classes

Spring includes a number of classes that can help with unit testing. They fall into two
categories:

* <<unit-testing-utilities>>
* <<unit-testing-spring-mvc>>


[[unit-testing-utilities]]
==== General Testing Utilities

The `org.springframework.test.util` package contains several general purpose utilities
for use in unit and integration testing.

`ReflectionTestUtils` is a collection of reflection-based utility methods. You can use
these methods in testing scenarios where you need to change the value of a constant, set
a non-`public` field, invoke a non-`public` setter method, or invoke a non-`public`
configuration or lifecycle callback method when testing application code for use cases
such as the following:

* ORM frameworks (such as JPA and Hibernate) that condone `private` or `protected` field
  access as opposed to `public` setter methods for properties in a domain entity.
* Spring's support for annotations (such as `@Autowired`, `@Inject`, and `@Resource`),
  that provide dependency injection for `private` or `protected` fields, setter methods,
  and configuration methods.
* Use of annotations such as `@PostConstruct` and `@PreDestroy` for lifecycle callback
  methods.

{api-spring-framework}/test/util/AopTestUtils.html[`AopTestUtils`] is a collection of
AOP-related utility methods. You can use these methods to obtain a reference to the
underlying target object hidden behind one or more Spring proxies. For example, if you
have configured a bean as a dynamic mock by using a library such as EasyMock or Mockito,
and the mock is wrapped in a Spring proxy, you may need direct access to the underlying
mock to configure expectations on it and perform verifications. For Spring's core AOP
utilities, see {api-spring-framework}/aop/support/AopUtils.html[`AopUtils`] and
{api-spring-framework}/aop/framework/AopProxyUtils.html[`AopProxyUtils`].


[[unit-testing-spring-mvc]]
==== Spring MVC Testing Utilities

The `org.springframework.test.web` package contains
{api-spring-framework}/test/web/ModelAndViewAssert.html[`ModelAndViewAssert`], which you
can use in combination with JUnit, TestNG, or any other testing framework for unit tests
that deal with Spring MVC `ModelAndView` objects.

.Unit testing Spring MVC Controllers
TIP: To unit test your Spring MVC `Controller` classes as POJOs, use `ModelAndViewAssert`
combined with `MockHttpServletRequest`, `MockHttpSession`, and so on from Spring's
<<mock-objects-servlet, Servlet API mocks>>. For thorough integration testing of your
Spring MVC and REST `Controller` classes in conjunction with your `WebApplicationContext`
configuration for Spring MVC, use the
<<spring-mvc-test-framework, Spring MVC Test Framework>> instead.




[[integration-testing]]
== Integration Testing

This section (most of the rest of this chapter) covers integration testing for Spring
applications. It includes the following topics:

* <<integration-testing-overview>>
* <<integration-testing-goals>>
* <<integration-testing-support-jdbc>>
* <<integration-testing-annotations>>
* <<testcontext-framework>>
* <<spring-mvc-test-framework>>



[[integration-testing-overview]]
=== Overview

It is important to be able to perform some integration testing without requiring
deployment to your application server or connecting to other enterprise infrastructure.
Doing so lets you test things such as:

* The correct wiring of your Spring IoC container contexts.
* Data access using JDBC or an ORM tool. This can include such things as the correctness
  of SQL statements, Hibernate queries, JPA entity mappings, and so forth.

The Spring Framework provides first-class support for integration testing in the
`spring-test` module. The name of the actual JAR file might include the release version
and might also be in the long `org.springframework.test` form, depending on where you get
it from (see the <<core.adoc#dependency-management, section on Dependency Management>>
for an explanation). This library includes the `org.springframework.test` package, which
contains valuable classes for integration testing with a Spring container. This testing
does not rely on an application server or other deployment environment. Such tests are
slower to run than unit tests but much faster than the equivalent Selenium tests or
remote tests that rely on deployment to an application server.

Unit and integration testing support is provided in the form of the annotation-driven
<<testcontext-framework, Spring TestContext Framework>>. The TestContext framework is
agnostic of the actual testing framework in use, which allows instrumentation of tests
in various environments, including JUnit, TestNG, and others.



[[integration-testing-goals]]
=== Goals of Integration Testing

Spring's integration testing support has the following primary goals:

* To manage <<testing-ctx-management, Spring IoC container caching>> between tests.
* To provide <<testing-fixture-di, Dependency Injection of test fixture instances>>.
* To provide <<testing-tx, transaction management>> appropriate to integration testing.
* To supply <<testing-support-classes, Spring-specific base classes>> that assist
  developers in writing integration tests.

The next few sections describe each goal and provide links to implementation and
configuration details.


[[testing-ctx-management]]
==== Context Management and Caching

The Spring TestContext Framework provides consistent loading of Spring
`ApplicationContext` instances and `WebApplicationContext` instances as well as caching
of those contexts. Support for the caching of loaded contexts is important, because
startup time can become an issue -- not because of the overhead of Spring itself, but
because the objects instantiated by the Spring container take time to instantiate. For
example, a project with 50 to 100 Hibernate mapping files might take 10 to 20 seconds to
load the mapping files, and incurring that cost before running every test in every test
fixture leads to slower overall test runs that reduce developer productivity.

Test classes typically declare either an array of resource locations for XML or Groovy
configuration metadata -- often in the classpath -- or an array of component classes that
is used to configure the application. These locations or classes are the same as or
similar to those specified in `web.xml` or other configuration files for production
deployments.

By default, once loaded, the configured `ApplicationContext` is reused for each test.
Thus, the setup cost is incurred only once per test suite, and subsequent test execution
is much faster. In this context, the term "`test suite`" means all tests run in the same
JVM -- for example, all tests run from an Ant, Maven, or Gradle build for a given project
or module. In the unlikely case that a test corrupts the application context and requires
reloading (for example, by modifying a bean definition or the state of an application
object) the TestContext framework can be configured to reload the configuration and
rebuild the application context before executing the next test.

See <<testcontext-ctx-management>> and <<testcontext-ctx-management-caching>> with the
TestContext framework.


[[testing-fixture-di]]
==== Dependency Injection of Test Fixtures

When the TestContext framework loads your application context, it can optionally
configure instances of your test classes by using Dependency Injection. This provides a
convenient mechanism for setting up test fixtures by using preconfigured beans from your
application context. A strong benefit here is that you can reuse application contexts
across various testing scenarios (for example, for configuring Spring-managed object
graphs, transactional proxies, `DataSource` instances, and others), thus avoiding the
need to duplicate complex test fixture setup for individual test cases.

As an example, consider a scenario where we have a class (`HibernateTitleRepository`)
that implements data access logic for a `Title` domain entity. We want to write
integration tests that test the following areas:

* The Spring configuration: Basically, is everything related to the configuration of the
  `HibernateTitleRepository` bean correct and present?
* The Hibernate mapping file configuration: Is everything mapped correctly and are the
  correct lazy-loading settings in place?
* The logic of the `HibernateTitleRepository`: Does the configured instance of this class
  perform as anticipated?

See dependency injection of test fixtures with the
<<testcontext-fixture-di, TestContext framework>>.


[[testing-tx]]
==== Transaction Management

One common issue in tests that access a real database is their effect on the state of the
persistence store. Even when you use a development database, changes to the state may
affect future tests. Also, many operations -- such as inserting or modifying persistent
data -- cannot be performed (or verified) outside of a transaction.

The TestContext framework addresses this issue. By default, the framework creates and
rolls back a transaction for each test. You can write code that can assume the existence
of a transaction. If you call transactionally proxied objects in your tests, they behave
correctly, according to their configured transactional semantics. In addition, if a test
method deletes the contents of selected tables while running within the transaction
managed for the test, the transaction rolls back by default, and the database returns to
its state prior to execution of the test. Transactional support is provided to a test by
using a `PlatformTransactionManager` bean defined in the test's application context.

If you want a transaction to commit (unusual, but occasionally useful when you want a
particular test to populate or modify the database), you can tell the TestContext
framework to cause the transaction to commit instead of roll back by using the
<<integration-testing-annotations, `@Commit`>> annotation.

See transaction management with the <<testcontext-tx, TestContext framework>>.


[[testing-support-classes]]
==== Support Classes for Integration Testing

The Spring TestContext Framework provides several `abstract` support classes that
simplify the writing of integration tests. These base test classes provide well-defined
hooks into the testing framework as well as convenient instance variables and methods,
which let you access:

* The `ApplicationContext`, for performing explicit bean lookups or testing the state of
  the context as a whole.
* A `JdbcTemplate`, for executing SQL statements to query the database. You can use such
  queries to confirm database state both before and after execution of database-related
  application code, and Spring ensures that such queries run in the scope of the same
  transaction as the application code. When used in conjunction with an ORM tool, be sure
  to avoid <<testcontext-tx-false-positives, false positives>>.

In addition, you may want to create your own custom, application-wide superclass with
instance variables and methods specific to your project.

See support classes for the <<testcontext-support-classes, TestContext framework>>.



[[integration-testing-support-jdbc]]
=== JDBC Testing Support

The `org.springframework.test.jdbc` package contains `JdbcTestUtils`, which is a
collection of JDBC-related utility functions intended to simplify standard database
testing scenarios. Specifically, `JdbcTestUtils` provides the following static utility
methods.

* `countRowsInTable(..)`: Counts the number of rows in the given table.
* `countRowsInTableWhere(..)`: Counts the number of rows in the given table by using the
  provided `WHERE` clause.
* `deleteFromTables(..)`: Deletes all rows from the specified tables.
* `deleteFromTableWhere(..)`: Deletes rows from the given table by using the provided
  `WHERE` clause.
* `dropTables(..)`: Drops the specified tables.

[TIP]
====
<<testcontext-support-classes-junit4, `AbstractTransactionalJUnit4SpringContextTests`>>
and <<testcontext-support-classes-testng, `AbstractTransactionalTestNGSpringContextTests`>>
provide convenience methods that delegate to the aforementioned methods in
`JdbcTestUtils`.

The `spring-jdbc` module provides support for configuring and launching an embedded
database, which you can use in integration tests that interact with a database.
For details, see <<data-access.adoc#jdbc-embedded-database-support, Embedded Database
Support>> and <<data-access.adoc#jdbc-embedded-database-dao-testing, Testing Data Access
Logic with an Embedded Database>>.
====



[[integration-testing-annotations]]
=== Annotations

This section covers annotations that you can use when you test Spring applications.
It includes the following topics:

* <<integration-testing-annotations-spring>>
* <<integration-testing-annotations-standard>>
* <<integration-testing-annotations-junit4>>
* <<integration-testing-annotations-junit-jupiter>>
* <<integration-testing-annotations-meta>>


[[integration-testing-annotations-spring]]
==== Spring Testing Annotations

The Spring Framework provides the following set of Spring-specific annotations that you
can use in your unit and integration tests in conjunction with the TestContext framework.
See the corresponding javadoc for further information, including default attribute
values, attribute aliases, and other details.

Spring's testing annotations include the following:

* <<spring-testing-annotation-bootstrapwith>>
* <<spring-testing-annotation-contextconfiguration>>
* <<spring-testing-annotation-webappconfiguration>>
* <<spring-testing-annotation-contexthierarchy>>
* <<spring-testing-annotation-activeprofiles>>
* <<spring-testing-annotation-testpropertysource>>
* <<spring-testing-annotation-dirtiescontext>>
* <<spring-testing-annotation-testexecutionlisteners>>
* <<spring-testing-annotation-commit>>
* <<spring-testing-annotation-rollback>>
* <<spring-testing-annotation-beforetransaction>>
* <<spring-testing-annotation-aftertransaction>>
* <<spring-testing-annotation-sql>>
* <<spring-testing-annotation-sqlconfig>>
* <<spring-testing-annotation-sqlmergemode>>
* <<spring-testing-annotation-sqlgroup>>

[[spring-testing-annotation-bootstrapwith]]
===== `@BootstrapWith`

`@BootstrapWith` is a class-level annotation that you can use to configure how the Spring
TestContext Framework is bootstrapped. Specifically, you can use `@BootstrapWith` to
specify a custom `TestContextBootstrapper`. See the section on
<<testcontext-bootstrapping, bootstrapping the TestContext framework>> for further details.

[[spring-testing-annotation-contextconfiguration]]
===== `@ContextConfiguration`

`@ContextConfiguration` defines class-level metadata that is used to determine how to
load and configure an `ApplicationContext` for integration tests. Specifically,
`@ContextConfiguration` declares the application context resource `locations` or the
component `classes` used to load the context.

Resource locations are typically XML configuration files or Groovy scripts located in the
classpath, while component classes are typically `@Configuration` classes. However,
resource locations can also refer to files and scripts in the file system, and component
classes can be `@Component` classes, `@Service` classes, and so on. See
<<testcontext-ctx-management-javaconfig-component-classes>> for further details.

The following example shows a `@ContextConfiguration` annotation that refers to an XML
file:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@ContextConfiguration("/test-config.xml") // <1>
	class XmlApplicationContextTests {
		// class body...
	}
----
<1> Referring to an XML file.

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@ContextConfiguration("/test-config.xml") // <1>
	class XmlApplicationContextTests {
		// class body...
	}
----
<1> Referring to an XML file.


The following example shows a `@ContextConfiguration` annotation that refers to a class:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@ContextConfiguration(classes = TestConfig.class) // <1>
	class ConfigClassApplicationContextTests {
		// class body...
	}
----
<1> Referring to a class.

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@ContextConfiguration(classes = [TestConfig::class]) // <1>
	class ConfigClassApplicationContextTests {
		// class body...
	}
----
<1> Referring to a class.


As an alternative or in addition to declaring resource locations or component classes,
you can use `@ContextConfiguration` to declare `ApplicationContextInitializer` classes.
The following example shows such a case:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@ContextConfiguration(initializers = CustomContextIntializer.class) // <1>
	class ContextInitializerTests {
		// class body...
	}
----

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@ContextConfiguration(initializers = [CustomContextIntializer::class]) // <1>
	class ContextInitializerTests {
		// class body...
	}
----
<1> Declaring an initializer class.


You can optionally use `@ContextConfiguration` to declare the `ContextLoader` strategy as
well. Note, however, that you typically do not need to explicitly configure the loader,
since the default loader supports `initializers` and either resource `locations` or
component `classes`.

The following example uses both a location and a loader:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@ContextConfiguration(locations = "/test-context.xml", loader = CustomContextLoader.class) // <1>
	class CustomLoaderXmlApplicationContextTests {
		// class body...
	}
----
<1> Configuring both a location and a custom loader.

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@ContextConfiguration("/test-context.xml", loader = CustomContextLoader::class) // <1>
	class CustomLoaderXmlApplicationContextTests {
		// class body...
	}
----
<1> Configuring both a location and a custom loader.


NOTE: `@ContextConfiguration` provides support for inheriting resource locations or
configuration classes as well as context initializers that are declared by superclasses.

See <<testcontext-ctx-management>> and the `@ContextConfiguration` javadocs for further
details.

[[spring-testing-annotation-webappconfiguration]]
===== `@WebAppConfiguration`

`@WebAppConfiguration` is a class-level annotation that you can use to declare that the
`ApplicationContext` loaded for an integration test should be a `WebApplicationContext`.
The mere presence of `@WebAppConfiguration` on a test class ensures that a
`WebApplicationContext` is loaded for the test, using the default value of
`"file:src/main/webapp"` for the path to the root of the web application (that is, the
resource base path). The resource base path is used behind the scenes to create a
`MockServletContext`, which serves as the `ServletContext` for the test's
`WebApplicationContext`.

The following example shows how to use the `@WebAppConfiguration` annotation:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@ContextConfiguration
	@WebAppConfiguration // <1>
	class WebAppTests {
		// class body...
	}
----

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@ContextConfiguration
	@WebAppConfiguration // <1>
	class WebAppTests {
		// class body...
	}
----
<1> The `@WebAppConfiguration` annotation.


To override the default, you can specify a different base resource path by using the
implicit `value` attribute. Both `classpath:` and `file:` resource prefixes are
supported. If no resource prefix is supplied, the path is assumed to be a file system
resource. The following example shows how to specify a classpath resource:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@ContextConfiguration
	@WebAppConfiguration("classpath:test-web-resources") // <1>
	class WebAppTests {
		// class body...
	}
----
<1> Specifying a classpath resource.

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@ContextConfiguration
	@WebAppConfiguration("classpath:test-web-resources") // <1>
	class WebAppTests {
		// class body...
	}
----
<1> Specifying a classpath resource.


Note that `@WebAppConfiguration` must be used in conjunction with
`@ContextConfiguration`, either within a single test class or within a test class
hierarchy. See the
{api-spring-framework}/test/context/web/WebAppConfiguration.html[`@WebAppConfiguration`]
javadoc for further details.

[[spring-testing-annotation-contexthierarchy]]
===== `@ContextHierarchy`

`@ContextHierarchy` is a class-level annotation that is used to define a hierarchy of
`ApplicationContext` instances for integration tests. `@ContextHierarchy` should be
declared with a list of one or more `@ContextConfiguration` instances, each of which
defines a level in the context hierarchy. The following examples demonstrate the use of
`@ContextHierarchy` within a single test class (`@ContextHierarchy` can also be used
within a test class hierarchy):

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@ContextHierarchy({
		@ContextConfiguration("/parent-config.xml"),
		@ContextConfiguration("/child-config.xml")
	})
	class ContextHierarchyTests {
		// class body...
	}
----
[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@ContextHierarchy(
		ContextConfiguration("/parent-config.xml"),
		ContextConfiguration("/child-config.xml"))
	class ContextHierarchyTests {
		// class body...
	}
----

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@WebAppConfiguration
	@ContextHierarchy({
		@ContextConfiguration(classes = AppConfig.class),
		@ContextConfiguration(classes = WebConfig.class)
	})
	class WebIntegrationTests {
		// class body...
	}
----
[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@WebAppConfiguration
	@ContextHierarchy(
			ContextConfiguration(classes = [AppConfig::class]),
			ContextConfiguration(classes = [WebConfig::class]))
	class WebIntegrationTests {
		// class body...
	}
----

If you need to merge or override the configuration for a given level of the context
hierarchy within a test class hierarchy, you must explicitly name that level by supplying
the same value to the `name` attribute in `@ContextConfiguration` at each corresponding
level in the class hierarchy. See <<testcontext-ctx-management-ctx-hierarchies>> and the
{api-spring-framework}/test/context/ContextHierarchy.html[`@ContextHierarchy`] javadoc
for further examples.

[[spring-testing-annotation-activeprofiles]]
===== `@ActiveProfiles`

`@ActiveProfiles` is a class-level annotation that is used to declare which bean
definition profiles should be active when loading an `ApplicationContext` for an
integration test.

The following example indicates that the `dev` profile should be active:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@ContextConfiguration
	@ActiveProfiles("dev") // <1>
	class DeveloperTests {
		// class body...
	}
----
<1> Indicate that the `dev` profile should be active.

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@ContextConfiguration
	@ActiveProfiles("dev") // <1>
	class DeveloperTests {
		// class body...
	}
----
<1> Indicate that the `dev` profile should be active.


The following example indicates that both the `dev` and the `integration` profiles should
be active:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@ContextConfiguration
	@ActiveProfiles({"dev", "integration"}) // <1>
	class DeveloperIntegrationTests {
		// class body...
	}
----
<1> Indicate that the `dev` and `integration` profiles should be active.

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@ContextConfiguration
	@ActiveProfiles(["dev", "integration"]) // <1>
	class DeveloperIntegrationTests {
		// class body...
	}
----
<1> Indicate that the `dev` and `integration` profiles should be active.


NOTE: `@ActiveProfiles` provides support for inheriting active bean definition profiles
declared by superclasses by default. You can also resolve active bean definition profiles
programmatically by implementing a custom
<<testcontext-ctx-management-env-profiles-ActiveProfilesResolver, `ActiveProfilesResolver`>>
and registering it by using the `resolver` attribute of `@ActiveProfiles`.

See <<testcontext-ctx-management-env-profiles>> and the
{api-spring-framework}/test/context/ActiveProfiles.html[`@ActiveProfiles`] javadoc for
examples and further details.

[[spring-testing-annotation-testpropertysource]]
===== `@TestPropertySource`

`@TestPropertySource` is a class-level annotation that you can use to configure the
locations of properties files and inlined properties to be added to the set of
`PropertySources` in the `Environment` for an `ApplicationContext` loaded for an
integration test.

Test property sources have higher precedence than those loaded from the operating
system's environment or Java system properties as well as property sources added by the
application declaratively through `@PropertySource` or programmatically. Thus, test
property sources can be used to selectively override properties defined in system and
application property sources. Furthermore, inlined properties have higher precedence than
properties loaded from resource locations.

The following example demonstrates how to declare a properties file from the classpath:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@ContextConfiguration
	@TestPropertySource("/test.properties") // <1>
	class MyIntegrationTests {
		// class body...
	}
----
<1> Get properties from `test.properties` in the root of the classpath.

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@ContextConfiguration
	@TestPropertySource("/test.properties") // <1>
	class MyIntegrationTests {
		// class body...
	}
----
<1> Get properties from `test.properties` in the root of the classpath.


The following example demonstrates how to declare inlined properties:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@ContextConfiguration
	@TestPropertySource(properties = { "timezone = GMT", "port: 4242" }) // <1>
	class MyIntegrationTests {
		// class body...
	}
----
<1> Declare `timezone` and `port` properties.

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@ContextConfiguration
	@TestPropertySource(properties = ["timezone = GMT", "port: 4242"]) // <1>
	class MyIntegrationTests {
		// class body...
	}
----
<1> Declare `timezone` and `port` properties.

See <<testcontext-ctx-management-property-sources>> for examples and further details.

[[spring-testing-annotation-dirtiescontext]]
===== `@DirtiesContext`

`@DirtiesContext` indicates that the underlying Spring `ApplicationContext` has been
dirtied during the execution of a test (that is, the test modified or corrupted it in
some manner -- for example, by changing the state of a singleton bean) and should be
closed. When an application context is marked as dirty, it is removed from the testing
framework's cache and closed. As a consequence, the underlying Spring container is
rebuilt for any subsequent test that requires a context with the same configuration
metadata.

You can use `@DirtiesContext` as both a class-level and a method-level annotation within
the same class or class hierarchy. In such scenarios, the `ApplicationContext` is marked
as dirty before or after any such annotated method as well as before or after the current
test class, depending on the configured `methodMode` and `classMode`.

The following examples explain when the context would be dirtied for various
configuration scenarios:

* Before the current test class, when declared on a class with class mode set to
`BEFORE_CLASS`.
+
[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@DirtiesContext(classMode = BEFORE_CLASS) // <1>
	class FreshContextTests {
		// some tests that require a new Spring container
	}
----
<1> Dirty the context before the current test class.
+
[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@DirtiesContext(classMode = BEFORE_CLASS) // <1>
	class FreshContextTests {
		// some tests that require a new Spring container
	}
----
<1> Dirty the context before the current test class.

* After the current test class, when declared on a class with class mode set to
`AFTER_CLASS` (i.e., the default class mode).
+
[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@DirtiesContext // <1>
	class ContextDirtyingTests {
		// some tests that result in the Spring container being dirtied
	}
----
<1> Dirty the context after the current test class.
+
[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@DirtiesContext // <1>
	class ContextDirtyingTests {
		// some tests that result in the Spring container being dirtied
	}
----
<1> Dirty the context after the current test class.


* Before each test method in the current test class, when declared on a class with class
mode set to `BEFORE_EACH_TEST_METHOD.`
+
[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@DirtiesContext(classMode = BEFORE_EACH_TEST_METHOD) // <1>
	class FreshContextTests {
		// some tests that require a new Spring container
	}
----
<1> Dirty the context before each test method.
+
[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@DirtiesContext(classMode = BEFORE_EACH_TEST_METHOD) // <1>
	class FreshContextTests {
		// some tests that require a new Spring container
	}
----
<1> Dirty the context before each test method.


* After each test method in the current test class, when declared on a class with class
mode set to `AFTER_EACH_TEST_METHOD.`
+
[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@DirtiesContext(classMode = AFTER_EACH_TEST_METHOD) // <1>
	class ContextDirtyingTests {
		// some tests that result in the Spring container being dirtied
	}
----
<1> Dirty the context after each test method.
+
[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@DirtiesContext(classMode = AFTER_EACH_TEST_METHOD) // <1>
	class ContextDirtyingTests {
		// some tests that result in the Spring container being dirtied
	}
----
<1> Dirty the context after each test method.


* Before the current test, when declared on a method with the method mode set to
`BEFORE_METHOD`.
+
[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@DirtiesContext(methodMode = BEFORE_METHOD) // <1>
	@Test
	void testProcessWhichRequiresFreshAppCtx() {
		// some logic that requires a new Spring container
	}
----
<1> Dirty the context before the current test method.
+
[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@DirtiesContext(methodMode = BEFORE_METHOD) // <1>
	@Test
	fun testProcessWhichRequiresFreshAppCtx() {
		// some logic that requires a new Spring container
	}
----
<1> Dirty the context before the current test method.

* After the current test, when declared on a method with the method mode set to
`AFTER_METHOD` (i.e., the default method mode).
+
[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@DirtiesContext // <1>
	@Test
	void testProcessWhichDirtiesAppCtx() {
		// some logic that results in the Spring container being dirtied
	}
----
<1> Dirty the context after the current test method.
+
[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@DirtiesContext // <1>
	@Test
	fun testProcessWhichDirtiesAppCtx() {
		// some logic that results in the Spring container being dirtied
	}
----
<1> Dirty the context after the current test method.


If you use `@DirtiesContext` in a test whose context is configured as part of a context
hierarchy with `@ContextHierarchy`, you can use the `hierarchyMode` flag to control how
the context cache is cleared. By default, an exhaustive algorithm is used to clear the
context cache, including not only the current level but also all other context
hierarchies that share an ancestor context common to the current test. All
`ApplicationContext` instances that reside in a sub-hierarchy of the common ancestor
context are removed from the context cache and closed. If the exhaustive algorithm is
overkill for a particular use case, you can specify the simpler current level algorithm,
as the following example shows.

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@ContextHierarchy({
		@ContextConfiguration("/parent-config.xml"),
		@ContextConfiguration("/child-config.xml")
	})
	class BaseTests {
		// class body...
	}

	class ExtendedTests extends BaseTests {

		@Test
		@DirtiesContext(hierarchyMode = CURRENT_LEVEL) // <1>
		void test() {
			// some logic that results in the child context being dirtied
		}
	}
----
<1> Use the current-level algorithm.

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@ContextHierarchy(
		ContextConfiguration("/parent-config.xml"),
		ContextConfiguration("/child-config.xml"))
	open class BaseTests {
		// class body...
	}

	class ExtendedTests : BaseTests() {

		@Test
		@DirtiesContext(hierarchyMode = CURRENT_LEVEL) // <1>
		fun test() {
			// some logic that results in the child context being dirtied
		}
	}
----
<1> Use the current-level algorithm.


For further details regarding the `EXHAUSTIVE` and `CURRENT_LEVEL` algorithms, see the
{api-spring-framework}/test/annotation/DirtiesContext.HierarchyMode.html[`DirtiesContext.HierarchyMode`]
javadoc.

[[spring-testing-annotation-testexecutionlisteners]]
===== `@TestExecutionListeners`

`@TestExecutionListeners` defines class-level metadata for configuring the
`TestExecutionListener` implementations that should be registered with the
`TestContextManager`. Typically, `@TestExecutionListeners` is used in conjunction with
`@ContextConfiguration`.

The following example shows how to register two `TestExecutionListener` implementations:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@ContextConfiguration
	@TestExecutionListeners({CustomTestExecutionListener.class, AnotherTestExecutionListener.class}) // <1>
	class CustomTestExecutionListenerTests {
		// class body...
	}
----
<1> Register two `TestExecutionListener` implementations.

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@ContextConfiguration
	@TestExecutionListeners(CustomTestExecutionListener::class, AnotherTestExecutionListener::class) // <1>
	class CustomTestExecutionListenerTests {
		// class body...
	}
----
<1> Register two `TestExecutionListener` implementations.


By default, `@TestExecutionListeners` supports inherited listeners. See the
{api-spring-framework}/test/context/TestExecutionListeners.html[javadoc]
for an example and further details.

[[spring-testing-annotation-commit]]
===== `@Commit`

`@Commit` indicates that the transaction for a transactional test method should be
committed after the test method has completed. You can use `@Commit` as a direct
replacement for `@Rollback(false)` to more explicitly convey the intent of the code.
Analogous to `@Rollback`, `@Commit` can also be declared as a class-level or method-level
annotation.

The following example shows how to use the `@Commit` annotation:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@Commit // <1>
	@Test
	void testProcessWithoutRollback() {
		// ...
	}
----
<1> Commit the result of the test to the database.

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@Commit // <1>
	@Test
	fun testProcessWithoutRollback() {
		// ...
	}
----
<1> Commit the result of the test to the database.


[[spring-testing-annotation-rollback]]
===== `@Rollback`

`@Rollback` indicates whether the transaction for a transactional test method should be
rolled back after the test method has completed. If `true`, the transaction is rolled
back. Otherwise, the transaction is committed (see also
<<spring-testing-annotation-commit>>). Rollback for integration tests in the Spring
TestContext Framework defaults to `true` even if `@Rollback` is not explicitly declared.

When declared as a class-level annotation, `@Rollback` defines the default rollback
semantics for all test methods within the test class hierarchy. When declared as a
method-level annotation, `@Rollback` defines rollback semantics for the specific test
method, potentially overriding class-level `@Rollback` or `@Commit` semantics.

The following example causes a test method's result to not be rolled back (that is, the
result is committed to the database):

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@Rollback(false) // <1>
	@Test
	void testProcessWithoutRollback() {
		// ...
	}
----
<1> Do not roll back the result.

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@Rollback(false) // <1>
	@Test
	fun testProcessWithoutRollback() {
		// ...
	}
----
<1> Do not roll back the result.


[[spring-testing-annotation-beforetransaction]]
===== `@BeforeTransaction`

`@BeforeTransaction` indicates that the annotated `void` method should be run before a
transaction is started, for test methods that have been configured to run within a
transaction by using Spring's `@Transactional` annotation. `@BeforeTransaction` methods
are not required to be `public` and may be declared on Java 8-based interface default
methods.

The following example shows how to use the `@BeforeTransaction` annotation:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@BeforeTransaction // <1>
	void beforeTransaction() {
		// logic to be executed before a transaction is started
	}
----
<1> Run this method before a transaction.

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@BeforeTransaction // <1>
	fun beforeTransaction() {
		// logic to be executed before a transaction is started
	}
----
<1> Run this method before a transaction.


[[spring-testing-annotation-aftertransaction]]
===== `@AfterTransaction`

`@AfterTransaction` indicates that the annotated `void` method should be run after a
transaction is ended, for test methods that have been configured to run within a
transaction by using Spring's `@Transactional` annotation. `@AfterTransaction` methods
are not required to be `public` and may be declared on Java 8-based interface default
methods.

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@AfterTransaction // <1>
	void afterTransaction() {
		// logic to be executed after a transaction has ended
	}
----
<1> Run this method after a transaction.

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@AfterTransaction // <1>
	fun afterTransaction() {
		// logic to be executed after a transaction has ended
	}
----
<1> Run this method after a transaction.


[[spring-testing-annotation-sql]]
===== `@Sql`

`@Sql` is used to annotate a test class or test method to configure SQL scripts to be run
against a given database during integration tests. The following example shows how to use
it:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@Test
	@Sql({"/test-schema.sql", "/test-user-data.sql"}) // <1>
	void userTest() {
		// execute code that relies on the test schema and test data
	}
----
<1> Run two scripts for this test.

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@Test
	@Sql("/test-schema.sql", "/test-user-data.sql") // <1>
	fun userTest() {
		// execute code that relies on the test schema and test data
	}
----
<1> Run two scripts for this test.

See <<testcontext-executing-sql-declaratively>> for further details.


[[spring-testing-annotation-sqlconfig]]
===== `@SqlConfig`

`@SqlConfig` defines metadata that is used to determine how to parse and run SQL scripts
configured with the `@Sql` annotation. The following example shows how to use it:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@Test
	@Sql(
		scripts = "/test-user-data.sql",
		config = @SqlConfig(commentPrefix = "`", separator = "@@") // <1>
	)
	void userTest() {
		// execute code that relies on the test data
	}
----
<1> Set the comment prefix and the separator in SQL scripts.

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@Test
	@Sql("/test-user-data.sql", config = SqlConfig(commentPrefix = "`", separator = "@@")) // <1>
	fun userTest() {
		// execute code that relies on the test data
	}
----
<1> Set the comment prefix and the separator in SQL scripts.

[[spring-testing-annotation-sqlmergemode]]
===== `@SqlMergeMode`

`@SqlMergeMode` is used to annotate a test class or test method to configure whether
method-level `@Sql` declarations are merged with class-level `@Sql` declarations. If
`@SqlMergeMode` is not declared on a test class or test method, the `OVERRIDE` merge mode
will be used by default. With the `OVERRIDE` mode, method-level `@Sql` declarations will
effectively override class-level `@Sql` declarations.

Note that a method-level `@SqlMergeMode` declaration overrides a class-level declaration.

The following example shows how to use `@SqlMergeMode` at the class level.

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@SpringJUnitConfig(TestConfig.class)
	@Sql("/test-schema.sql")
	@SqlMergeMode(MERGE) // <1>
	class UserTests {

		@Test
		@Sql("/user-test-data-001.sql")
		void standardUserProfile() {
			// execute code that relies on test data set 001
		}
	}
----
<1> Set the `@Sql` merge mode to `MERGE` for all test methods in the class.

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@SpringJUnitConfig(TestConfig::class)
	@Sql("/test-schema.sql")
	@SqlMergeMode(MERGE) // <1>
	class UserTests {

		@Test
		@Sql("/user-test-data-001.sql")
		fun standardUserProfile() {
			// execute code that relies on test data set 001
		}
	}
----
<1> Set the `@Sql` merge mode to `MERGE` for all test methods in the class.

The following example shows how to use `@SqlMergeMode` at the method level.

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@SpringJUnitConfig(TestConfig.class)
	@Sql("/test-schema.sql")
	class UserTests {

		@Test
		@Sql("/user-test-data-001.sql")
		@SqlMergeMode(MERGE) // <1>
		void standardUserProfile() {
			// execute code that relies on test data set 001
		}
	}
----
<1> Set the `@Sql` merge mode to `MERGE` for a specific test method.

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@SpringJUnitConfig(TestConfig::class)
	@Sql("/test-schema.sql")
	class UserTests {

		@Test
		@Sql("/user-test-data-001.sql")
		@SqlMergeMode(MERGE) // <1>
		fun standardUserProfile() {
			// execute code that relies on test data set 001
		}
	}
----
<1> Set the `@Sql` merge mode to `MERGE` for a specific test method.


[[spring-testing-annotation-sqlgroup]]
===== `@SqlGroup`

`@SqlGroup` is a container annotation that aggregates several `@Sql` annotations. You can
use `@SqlGroup` natively to declare several nested `@Sql` annotations, or you can use it
in conjunction with Java 8's support for repeatable annotations, where `@Sql` can be
declared several times on the same class or method, implicitly generating this container
annotation. The following example shows how to declare an SQL group:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@Test
	@SqlGroup({ // <1>
		@Sql(scripts = "/test-schema.sql", config = @SqlConfig(commentPrefix = "`")),
		@Sql("/test-user-data.sql")
	)}
	void userTest() {
		// execute code that uses the test schema and test data
	}
----
<1> Declare a group of SQL scripts.

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@Test
	@SqlGroup( // <1>
		Sql("/test-schema.sql", config = SqlConfig(commentPrefix = "`")),
		Sql("/test-user-data.sql"))
	fun userTest() {
		// execute code that uses the test schema and test data
	}
----
<1> Declare a group of SQL scripts.

[[integration-testing-annotations-standard]]
==== Standard Annotation Support

The following annotations are supported with standard semantics for all configurations of
the Spring TestContext Framework. Note that these annotations are not specific to tests
and can be used anywhere in the Spring Framework.

* `@Autowired`
* `@Qualifier`
* `@Value`
* `@Resource` (javax.annotation) if JSR-250 is present
* `@ManagedBean` (javax.annotation) if JSR-250 is present
* `@Inject` (javax.inject) if JSR-330 is present
* `@Named` (javax.inject) if JSR-330 is present
* `@PersistenceContext` (javax.persistence) if JPA is present
* `@PersistenceUnit` (javax.persistence) if JPA is present
* `@Required`
* `@Transactional` (org.springframework.transaction.annotation)
  _with <<testcontext-tx-attribute-support, limited attribute support>>_

.JSR-250 Lifecycle Annotations
[NOTE]
====
In the Spring TestContext Framework, you can use `@PostConstruct` and `@PreDestroy` with
standard semantics on any application components configured in the `ApplicationContext`.
However, these lifecycle annotations have limited usage within an actual test class.

If a method within a test class is annotated with `@PostConstruct`, that method runs
before any before methods of the underlying test framework (for example, methods
annotated with JUnit Jupiter's `@BeforeEach`), and that applies for every test method in
the test class. On the other hand, if a method within a test class is annotated with
`@PreDestroy`, that method never runs. Therefore, within a test class, we recommend that
you use test lifecycle callbacks from the underlying test framework instead of
`@PostConstruct` and `@PreDestroy`.
====


[[integration-testing-annotations-junit4]]
==== Spring JUnit 4 Testing Annotations

The following annotations are supported only when used in conjunction with the
<<testcontext-junit4-runner, SpringRunner>>, <<testcontext-junit4-rules, Spring's JUnit 4
rules>>, or <<testcontext-support-classes-junit4, Spring's JUnit 4 support classes>>:

* <<integration-testing-annotations-junit4-ifprofilevalue>>
* <<integration-testing-annotations-junit4-profilevaluesourceconfiguration>>
* <<integration-testing-annotations-junit4-timed>>
* <<integration-testing-annotations-junit4-repeat>>

[[integration-testing-annotations-junit4-ifprofilevalue]]
===== `@IfProfileValue`

`@IfProfileValue` indicates that the annotated test is enabled for a specific testing
environment. If the configured `ProfileValueSource` returns a matching `value` for the
provided `name`, the test is enabled. Otherwise, the test is disabled and, effectively,
ignored.

You can apply `@IfProfileValue` at the class level, the method level, or both.
Class-level usage of `@IfProfileValue` takes precedence over method-level usage for any
methods within that class or its subclasses. Specifically, a test is enabled if it is
enabled both at the class level and at the method level. The absence of `@IfProfileValue`
means the test is implicitly enabled. This is analogous to the semantics of JUnit 4's
`@Ignore` annotation, except that the presence of `@Ignore` always disables a test.

The following example shows a test that has an `@IfProfileValue` annotation:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@IfProfileValue(name="java.vendor", value="Oracle Corporation") // <1>
	@Test
	public void testProcessWhichRunsOnlyOnOracleJvm() {
		// some logic that should run only on Java VMs from Oracle Corporation
	}
----
<1> Run this test only when the Java vendor is "Oracle Corporation".

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@IfProfileValue(name="java.vendor", value="Oracle Corporation") // <1>
	@Test
	fun testProcessWhichRunsOnlyOnOracleJvm() {
		// some logic that should run only on Java VMs from Oracle Corporation
	}
----
<1> Run this test only when the Java vendor is "Oracle Corporation".


Alternatively, you can configure `@IfProfileValue` with a list of `values` (with `OR`
semantics) to achieve TestNG-like support for test groups in a JUnit 4 environment.
Consider the following example:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@IfProfileValue(name="test-groups", values={"unit-tests", "integration-tests"}) // <1>
	@Test
	public void testProcessWhichRunsForUnitOrIntegrationTestGroups() {
		// some logic that should run only for unit and integration test groups
	}
----
<1> Run this test for unit tests and integration tests.

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@IfProfileValue(name="test-groups", values=["unit-tests", "integration-tests"]) // <1>
	@Test
	fun testProcessWhichRunsForUnitOrIntegrationTestGroups() {
		// some logic that should run only for unit and integration test groups
	}
----
<1> Run this test for unit tests and integration tests.


[[integration-testing-annotations-junit4-profilevaluesourceconfiguration]]
===== `@ProfileValueSourceConfiguration`

`@ProfileValueSourceConfiguration` is a class-level annotation that specifies what type
of `ProfileValueSource` to use when retrieving profile values configured through the
`@IfProfileValue` annotation. If `@ProfileValueSourceConfiguration` is not declared for a
test, `SystemProfileValueSource` is used by default. The following example shows how to
use `@ProfileValueSourceConfiguration`:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@ProfileValueSourceConfiguration(CustomProfileValueSource.class) // <1>
	public class CustomProfileValueSourceTests {
		// class body...
	}
----
<1> Use a custom profile value source.

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@ProfileValueSourceConfiguration(CustomProfileValueSource::class) // <1>
	class CustomProfileValueSourceTests {
		// class body...
	}
----
<1> Use a custom profile value source.


[[integration-testing-annotations-junit4-timed]]
===== `@Timed`

`@Timed` indicates that the annotated test method must finish execution in a specified
time period (in milliseconds). If the text execution time exceeds the specified time
period, the test fails.

The time period includes running the test method itself, any repetitions of the test (see
`@Repeat`), as well as any setting up or tearing down of the test fixture. The following
example shows how to use it:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@Timed(millis = 1000) // <1>
	public void testProcessWithOneSecondTimeout() {
		// some logic that should not take longer than 1 second to execute
	}
----
<1> Set the time period for the test to one second.

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@Timed(millis = 1000) // <1>
	fun testProcessWithOneSecondTimeout() {
		// some logic that should not take longer than 1 second to execute
	}
----
<1> Set the time period for the test to one second.


Spring's `@Timed` annotation has different semantics than JUnit 4's `@Test(timeout=...)`
support. Specifically, due to the manner in which JUnit 4 handles test execution timeouts
(that is, by executing the test method in a separate `Thread`), `@Test(timeout=...)`
preemptively fails the test if the test takes too long. Spring's `@Timed`, on the other
hand, does not preemptively fail the test but rather waits for the test to complete
before failing.

[[integration-testing-annotations-junit4-repeat]]
===== `@Repeat`

`@Repeat` indicates that the annotated test method must be run repeatedly. The number of
times that the test method is to be executed is specified in the annotation.

The scope of execution to be repeated includes execution of the test method itself as
well as any setting up or tearing down of the test fixture. The following example shows
how to use the `@Repeat` annotation:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@Repeat(10) // <1>
	@Test
	public void testProcessRepeatedly() {
		// ...
	}
----
<1> Repeat this test ten times.

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@Repeat(10) // <1>
	@Test
	fun testProcessRepeatedly() {
		// ...
	}
----
<1> Repeat this test ten times.



[[integration-testing-annotations-junit-jupiter]]
==== Spring JUnit Jupiter Testing Annotations

The following annotations are supported only when used in conjunction with the
<<testcontext-junit-jupiter-extension, `SpringExtension`>> and JUnit Jupiter
(that is, the programming model in JUnit 5):

* <<integration-testing-annotations-junit-jupiter-springjunitconfig>>
* <<integration-testing-annotations-junit-jupiter-springjunitwebconfig>>
* <<integration-testing-annotations-testconstructor>>
* <<integration-testing-annotations-junit-jupiter-enabledif>>
* <<integration-testing-annotations-junit-jupiter-disabledif>>

[[integration-testing-annotations-junit-jupiter-springjunitconfig]]
===== `@SpringJUnitConfig`

`@SpringJUnitConfig` is a composed annotation that combines
`@ExtendWith(SpringExtension.class)` from JUnit Jupiter with `@ContextConfiguration` from
the Spring TestContext Framework. It can be used at the class level as a drop-in
replacement for `@ContextConfiguration`. With regard to configuration options, the only
difference between `@ContextConfiguration` and `@SpringJUnitConfig` is that component
classes may be declared with the `value` attribute in `@SpringJUnitConfig`.

The following example shows how to use the `@SpringJUnitConfig` annotation to specify a
configuration class:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@SpringJUnitConfig(TestConfig.class) // <1>
	class ConfigurationClassJUnitJupiterSpringTests {
		// class body...
	}
----
<1> Specify the configuration class.

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@SpringJUnitConfig(TestConfig::class) // <1>
	class ConfigurationClassJUnitJupiterSpringTests {
		// class body...
	}
----
<1> Specify the configuration class.


The following example shows how to use the `@SpringJUnitConfig` annotation to specify the
location of a configuration file:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@SpringJUnitConfig(locations = "/test-config.xml") // <1>
	class XmlJUnitJupiterSpringTests {
		// class body...
	}
----
<1> Specify the location of a configuration file.

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@SpringJUnitConfig(locations = ["/test-config.xml"]) // <1>
	class XmlJUnitJupiterSpringTests {
		// class body...
	}
----
<1> Specify the location of a configuration file.


See <<testcontext-ctx-management>> as well as the javadoc for
{api-spring-framework}/test/context/junit/jupiter/SpringJUnitConfig.html[`@SpringJUnitConfig`]
and `@ContextConfiguration` for further details.

[[integration-testing-annotations-junit-jupiter-springjunitwebconfig]]
===== `@SpringJUnitWebConfig`

`@SpringJUnitWebConfig` is a composed annotation that combines
`@ExtendWith(SpringExtension.class)` from JUnit Jupiter with `@ContextConfiguration` and
`@WebAppConfiguration` from the Spring TestContext Framework. You can use it at the class
level as a drop-in replacement for `@ContextConfiguration` and `@WebAppConfiguration`.
With regard to configuration options, the only difference between `@ContextConfiguration`
and `@SpringJUnitWebConfig` is that you can declare component classes by using the
`value` attribute in `@SpringJUnitWebConfig`. In addition, you can override the `value`
attribute from `@WebAppConfiguration` only by using the `resourcePath` attribute in
`@SpringJUnitWebConfig`.

The following example shows how to use the `@SpringJUnitWebConfig` annotation to specify
a configuration class:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@SpringJUnitWebConfig(TestConfig.class) // <1>
	class ConfigurationClassJUnitJupiterSpringWebTests {
		// class body...
	}
----
<1> Specify the configuration class.

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@SpringJUnitWebConfig(TestConfig::class) // <1>
	class ConfigurationClassJUnitJupiterSpringWebTests {
		// class body...
	}
----
<1> Specify the configuration class.


The following example shows how to use the `@SpringJUnitWebConfig` annotation to specify a
the location of a configuration file:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@SpringJUnitWebConfig(locations = "/test-config.xml") // <1>
	class XmlJUnitJupiterSpringWebTests {
		// class body...
	}
----
<1> Specify the location of a configuration file.

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@SpringJUnitWebConfig(locations = ["/test-config.xml"]) // <1>
	class XmlJUnitJupiterSpringWebTests {
		// class body...
	}
----
<1> Specify the location of a configuration file.


See <<testcontext-ctx-management>> as well as the javadoc for
{api-spring-framework}/test/context/junit/jupiter/web/SpringJUnitWebConfig.html[`@SpringJUnitWebConfig`],
{api-spring-framework}/test/context/ContextConfiguration.html[`@ContextConfiguration`], and
{api-spring-framework}/test/context/web/WebAppConfiguration.html[`@WebAppConfiguration`]
for further details.

[[integration-testing-annotations-testconstructor]]
===== `@TestConstructor`

`@TestConstructor` is a type-level annotation that is used to configure how the parameters
of a test class constructor are autowired from components in the test's
`ApplicationContext`.

If `@TestConstructor` is not present or meta-present on a test class, the default _test
constructor autowire mode_ will be used. See the tip below for details on how to change
the default mode. Note, however, that a local declaration of `@Autowired` on a
constructor takes precedence over both `@TestConstructor` and the default mode.

.Changing the default test constructor autowire mode
[TIP]
=====
The default _test constructor autowire mode_ can be changed by setting the
`spring.test.constructor.autowire.mode` JVM system property to `all`. Alternatively, the
default mode may be changed via the `SpringProperties` mechanism.

If the `spring.test.constructor.autowire.mode` property is not set, test class
constructors will not be automatically autowired.
=====

NOTE: As of Spring Framework 5.2, `@TestConstructor` is only supported in conjunction
with the `SpringExtension` for use with JUnit Jupiter. Note that the `SpringExtension` is
often automatically registered for you – for example, when using annotations such as
`@SpringJUnitConfig` and `@SpringJUnitWebConfig` or various test-related annotations from
Spring Boot Test.

[[integration-testing-annotations-junit-jupiter-enabledif]]
===== `@EnabledIf`

`@EnabledIf` is used to signal that the annotated JUnit Jupiter test class or test method
is enabled and should be run if the supplied `expression` evaluates to `true`.
Specifically, if the expression evaluates to `Boolean.TRUE` or a `String` equal to `true`
(ignoring case), the test is enabled. When applied at the class level, all test methods
within that class are automatically enabled by default as well.

Expressions can be any of the following:

* <<core.adoc#expressions, Spring Expression Language>> (SpEL) expression. For example:
  `@EnabledIf("#{systemProperties['os.name'].toLowerCase().contains('mac')}")`
* Placeholder for a property available in the Spring <<core.adoc#beans-environment, `Environment`>>.
  For example: `@EnabledIf("${smoke.tests.enabled}")`
* Text literal. For example: `@EnabledIf("true")`

Note, however, that a text literal that is not the result of dynamic resolution of a
property placeholder is of zero practical value, since `@EnabledIf("false")` is
equivalent to `@Disabled` and `@EnabledIf("true")` is logically meaningless.

You can use `@EnabledIf` as a meta-annotation to create custom composed annotations. For
example, you can create a custom `@EnabledOnMac` annotation as follows:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@Target({ElementType.TYPE, ElementType.METHOD})
	@Retention(RetentionPolicy.RUNTIME)
	@EnabledIf(
		expression = "#{systemProperties['os.name'].toLowerCase().contains('mac')}",
		reason = "Enabled on Mac OS"
	)
	public @interface EnabledOnMac {}
----
[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@Target(AnnotationTarget.TYPE, AnnotationTarget.FUNCTION)
	@Retention(AnnotationRetention.RUNTIME)
	@EnabledIf(
			expression = "#{systemProperties['os.name'].toLowerCase().contains('mac')}",
			reason = "Enabled on Mac OS"
	)
	annotation class EnabledOnMac {}
----

[[integration-testing-annotations-junit-jupiter-disabledif]]
===== `@DisabledIf`

`@DisabledIf` is used to signal that the annotated JUnit Jupiter test class or test
method is disabled and should not be executed if the supplied `expression` evaluates to
`true`. Specifically, if the expression evaluates to `Boolean.TRUE` or a `String` equal
to `true` (ignoring case), the test is disabled. When applied at the class level, all
test methods within that class are automatically disabled as well.

Expressions can be any of the following:

* <<core.adoc#expressions, Spring Expression Language>> (SpEL) expression. For example:
  `@DisabledIf("#{systemProperties['os.name'].toLowerCase().contains('mac')}")`
* Placeholder for a property available in the Spring <<core.adoc#beans-environment, `Environment`>>.
  For example: `@DisabledIf("${smoke.tests.disabled}")`
* Text literal. For example: `@DisabledIf("true")`

Note, however, that a text literal that is not the result of dynamic resolution of a
property placeholder is of zero practical value, since `@DisabledIf("true")` is
equivalent to `@Disabled` and `@DisabledIf("false")` is logically meaningless.

You can use `@DisabledIf` as a meta-annotation to create custom composed annotations. For
example, you can create a custom `@DisabledOnMac` annotation as follows:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@Target({ElementType.TYPE, ElementType.METHOD})
	@Retention(RetentionPolicy.RUNTIME)
	@DisabledIf(
		expression = "#{systemProperties['os.name'].toLowerCase().contains('mac')}",
		reason = "Disabled on Mac OS"
	)
	public @interface DisabledOnMac {}
----

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@Target(AnnotationTarget.TYPE, AnnotationTarget.FUNCTION)
	@Retention(AnnotationRetention.RUNTIME)
	@DisabledIf(
			expression = "#{systemProperties['os.name'].toLowerCase().contains('mac')}",
			reason = "Disabled on Mac OS"
	)
	annotation class DisabledOnMac {}
----

[[integration-testing-annotations-meta]]
==== Meta-Annotation Support for Testing

You can use most test-related annotations as
<<core.adoc#beans-meta-annotations, meta-annotations>> to create custom composed
annotations and reduce configuration duplication across a test suite.

You can use each of the following as a meta-annotation in conjunction with the
<<testcontext-framework, TestContext framework>>.

* `@BootstrapWith`
* `@ContextConfiguration`
* `@ContextHierarchy`
* `@ActiveProfiles`
* `@TestPropertySource`
* `@DirtiesContext`
* `@WebAppConfiguration`
* `@TestExecutionListeners`
* `@Transactional`
* `@BeforeTransaction`
* `@AfterTransaction`
* `@Commit`
* `@Rollback`
* `@Sql`
* `@SqlConfig`
* `@SqlMergeMode`
* `@SqlGroup`
* `@Repeat` _(only supported on JUnit 4)_
* `@Timed` _(only supported on JUnit 4)_
* `@IfProfileValue` _(only supported on JUnit 4)_
* `@ProfileValueSourceConfiguration` _(only supported on JUnit 4)_
* `@SpringJUnitConfig` _(only supported on JUnit Jupiter)_
* `@SpringJUnitWebConfig` _(only supported on JUnit Jupiter)_
* `@TestConstructor` _(only supported on JUnit Jupiter)_
* `@EnabledIf` _(only supported on JUnit Jupiter)_
* `@DisabledIf` _(only supported on JUnit Jupiter)_

Consider the following example:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@RunWith(SpringRunner.class)
	@ContextConfiguration({"/app-config.xml", "/test-data-access-config.xml"})
	@ActiveProfiles("dev")
	@Transactional
	public class OrderRepositoryTests { }

	@RunWith(SpringRunner.class)
	@ContextConfiguration({"/app-config.xml", "/test-data-access-config.xml"})
	@ActiveProfiles("dev")
	@Transactional
	public class UserRepositoryTests { }
----

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@RunWith(SpringRunner::class)
	@ContextConfiguration("/app-config.xml", "/test-data-access-config.xml")
	@ActiveProfiles("dev")
	@Transactional
	class OrderRepositoryTests { }

	@RunWith(SpringRunner::class)
	@ContextConfiguration("/app-config.xml", "/test-data-access-config.xml")
	@ActiveProfiles("dev")
	@Transactional
	class UserRepositoryTests { }
----

If we discover that we are repeating the preceding configuration across our JUnit 4-based
test suite, we can reduce the duplication by introducing a custom composed annotation
that centralizes the common test configuration for Spring, as follows:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@Target(ElementType.TYPE)
	@Retention(RetentionPolicy.RUNTIME)
	@ContextConfiguration({"/app-config.xml", "/test-data-access-config.xml"})
	@ActiveProfiles("dev")
	@Transactional
	public @interface TransactionalDevTestConfig { }
----

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@Target(AnnotationTarget.TYPE)
	@Retention(AnnotationRetention.RUNTIME)
	@ContextConfiguration("/app-config.xml", "/test-data-access-config.xml")
	@ActiveProfiles("dev")
	@Transactional
	annotation class TransactionalDevTestConfig { }
----

Then we can use our custom `@TransactionalDevTestConfig` annotation to simplify the
configuration of individual JUnit 4 based test classes, as follows:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@RunWith(SpringRunner.class)
	@TransactionalDevTestConfig
	public class OrderRepositoryTests { }

	@RunWith(SpringRunner.class)
	@TransactionalDevTestConfig
	public class UserRepositoryTests { }
----

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@RunWith(SpringRunner::class)
	@TransactionalDevTestConfig
	class OrderRepositoryTests

	@RunWith(SpringRunner::class)
	@TransactionalDevTestConfig
	class UserRepositoryTests
----

If we write tests that use JUnit Jupiter, we can reduce code duplication even further,
since annotations in JUnit 5 can also be used as meta-annotations. Consider the following
example:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@ExtendWith(SpringExtension.class)
	@ContextConfiguration({"/app-config.xml", "/test-data-access-config.xml"})
	@ActiveProfiles("dev")
	@Transactional
	class OrderRepositoryTests { }

	@ExtendWith(SpringExtension.class)
	@ContextConfiguration({"/app-config.xml", "/test-data-access-config.xml"})
	@ActiveProfiles("dev")
	@Transactional
	class UserRepositoryTests { }
----
[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@ExtendWith(SpringExtension::class)
	@ContextConfiguration("/app-config.xml", "/test-data-access-config.xml")
	@ActiveProfiles("dev")
	@Transactional
	class OrderRepositoryTests { }

	@ExtendWith(SpringExtension::class)
	@ContextConfiguration("/app-config.xml", "/test-data-access-config.xml")
	@ActiveProfiles("dev")
	@Transactional
	class UserRepositoryTests { }
----

If we discover that we are repeating the preceding configuration across our JUnit
Jupiter-based test suite, we can reduce the duplication by introducing a custom composed
annotation that centralizes the common test configuration for Spring and JUnit Jupiter,
as follows:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@Target(ElementType.TYPE)
	@Retention(RetentionPolicy.RUNTIME)
	@ExtendWith(SpringExtension.class)
	@ContextConfiguration({"/app-config.xml", "/test-data-access-config.xml"})
	@ActiveProfiles("dev")
	@Transactional
	public @interface TransactionalDevTestConfig { }
----
[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@Target(AnnotationTarget.TYPE)
	@Retention(AnnotationRetention.RUNTIME)
	@ExtendWith(SpringExtension::class)
	@ContextConfiguration("/app-config.xml", "/test-data-access-config.xml")
	@ActiveProfiles("dev")
	@Transactional
	annotation class TransactionalDevTestConfig { }
----

Then we can use our custom `@TransactionalDevTestConfig` annotation to simplify the
configuration of individual JUnit Jupiter based test classes, as follows:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@TransactionalDevTestConfig
	class OrderRepositoryTests { }

	@TransactionalDevTestConfig
	class UserRepositoryTests { }
----
[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@TransactionalDevTestConfig
	class OrderRepositoryTests { }

	@TransactionalDevTestConfig
	class UserRepositoryTests { }
----

Since JUnit Jupiter supports the use of `@Test`, `@RepeatedTest`, `ParameterizedTest`,
and others as meta-annotations, you can also create custom composed annotations at the
test method level. For example, if we wish to create a composed annotation that combines
the `@Test` and `@Tag` annotations from JUnit Jupiter with the `@Transactional`
annotation from Spring, we could create an `@TransactionalIntegrationTest` annotation, as
follows:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@Target(ElementType.METHOD)
	@Retention(RetentionPolicy.RUNTIME)
	@Transactional
	@Tag("integration-test") // org.junit.jupiter.api.Tag
	@Test // org.junit.jupiter.api.Test
	public @interface TransactionalIntegrationTest { }
----
[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@Target(AnnotationTarget.TYPE)
	@Retention(AnnotationRetention.RUNTIME)
	@Transactional
	@Tag("integration-test") // org.junit.jupiter.api.Tag
	@Test // org.junit.jupiter.api.Test
	annotation class TransactionalIntegrationTest { }
----

Then we can use our custom `@TransactionalIntegrationTest` annotation to simplify the
configuration of individual JUnit Jupiter based test methods, as follows:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@TransactionalIntegrationTest
	void saveOrder() { }

	@TransactionalIntegrationTest
	void deleteOrder() { }
----

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@TransactionalIntegrationTest
	fun saveOrder() { }

	@TransactionalIntegrationTest
	fun deleteOrder() { }
----

For further details, see the
https://github.com/spring-projects/spring-framework/wiki/Spring-Annotation-Programming-Model[Spring Annotation Programming Model]
wiki page.



[[testcontext-framework]]
=== Spring TestContext Framework

The Spring TestContext Framework (located in the `org.springframework.test.context`
package) provides generic, annotation-driven unit and integration testing support that is
agnostic of the testing framework in use. The TestContext framework also places a great
deal of importance on convention over configuration, with reasonable defaults that you
can override through annotation-based configuration.

In addition to generic testing infrastructure, the TestContext framework provides
explicit support for JUnit 4, JUnit Jupiter (AKA JUnit 5), and TestNG. For JUnit 4 and
TestNG, Spring provides `abstract` support classes. Furthermore, Spring provides a custom
JUnit `Runner` and custom JUnit `Rules` for JUnit 4 and a custom `Extension` for JUnit
Jupiter that let you write so-called POJO test classes. POJO test classes are not
required to extend a particular class hierarchy, such as the `abstract` support classes.

The following section provides an overview of the internals of the TestContext framework.
If you are interested only in using the framework and are not interested in extending it
with your own custom listeners or custom loaders, feel free to go directly to the
configuration (<<testcontext-ctx-management, context management>>,
<<testcontext-fixture-di, dependency injection>>, <<testcontext-tx,transaction
management>>), <<testcontext-support-classes, support classes>>, and
<<integration-testing-annotations, annotation support>> sections.


[[testcontext-key-abstractions]]
==== Key Abstractions

The core of the framework consists of the `TestContextManager` class and the
`TestContext`, `TestExecutionListener`, and `SmartContextLoader` interfaces. A
`TestContextManager` is created for each test class (for example, for the execution of
all test methods within a single test class in JUnit Jupiter). The `TestContextManager`,
in turn, manages a `TestContext` that holds the context of the current test. The
`TestContextManager` also updates the state of the `TestContext` as the test progresses
and delegates to `TestExecutionListener` implementations, which instrument the actual
test execution by providing dependency injection, managing transactions, and so on. A
`SmartContextLoader` is responsible for loading an `ApplicationContext` for a given test
class. See the {api-spring-framework}/test/context/package-summary.html[javadoc] and the
Spring test suite for further information and examples of various implementations.

===== `TestContext`

`TestContext` encapsulates the context in which a test is executed (agnostic of the
actual testing framework in use) and provides context management and caching support for
the test instance for which it is responsible. The `TestContext` also delegates to a
`SmartContextLoader` to load an `ApplicationContext` if requested.

===== `TestContextManager`

`TestContextManager` is the main entry point into the Spring TestContext Framework and is
responsible for managing a single `TestContext` and signaling events to each registered
`TestExecutionListener` at well-defined test execution points:

* Prior to any "`before class`" or "`before all`" methods of a particular testing framework.
* Test instance post-processing.
* Prior to any "`before`" or "`before each`" methods of a particular testing framework.
* Immediately before execution of the test method but after test setup.
* Immediately after execution of the test method but before test tear down.
* After any "`after`" or "`after each`" methods of a particular testing framework.
* After any "`after class`" or "`after all`" methods of a particular testing framework.

===== `TestExecutionListener`

`TestExecutionListener` defines the API for reacting to test-execution events published by
the `TestContextManager` with which the listener is registered. See <<testcontext-tel-config>>.

===== Context Loaders

`ContextLoader` is a strategy interface for loading an `ApplicationContext` for an
integration test managed by the Spring TestContext Framework. You should implement
`SmartContextLoader` instead of this interface to provide support for component classes,
active bean definition profiles, test property sources, context hierarchies, and
`WebApplicationContext` support.

`SmartContextLoader` is an extension of the `ContextLoader` interface that supersedes the
original minimal `ContextLoader` SPI. Specifically, a `SmartContextLoader` can choose to
process resource locations, component classes, or context initializers. Furthermore, a
`SmartContextLoader` can set active bean definition profiles and test property sources in
the context that it loads.

Spring provides the following implementations:

* `DelegatingSmartContextLoader`: One of two default loaders, it delegates internally to
  an `AnnotationConfigContextLoader`, a `GenericXmlContextLoader`, or a
  `GenericGroovyXmlContextLoader`, depending either on the configuration declared for the
  test class or on the presence of default locations or default configuration classes.
  Groovy support is enabled only if Groovy is on the classpath.
* `WebDelegatingSmartContextLoader`: One of two default loaders, it delegates internally
  to an `AnnotationConfigWebContextLoader`, a `GenericXmlWebContextLoader`, or a
  `GenericGroovyXmlWebContextLoader`, depending either on the configuration declared for
  the test class or on the presence of default locations or default configuration
  classes. A web `ContextLoader` is used only if `@WebAppConfiguration` is present on the
  test class. Groovy support is enabled only if Groovy is on the classpath.
* `AnnotationConfigContextLoader`: Loads a standard `ApplicationContext` from component
  classes.
* `AnnotationConfigWebContextLoader`: Loads a `WebApplicationContext` from component
  classes.
* `GenericGroovyXmlContextLoader`: Loads a standard `ApplicationContext` from resource
  locations that are either Groovy scripts or XML configuration files.
* `GenericGroovyXmlWebContextLoader`: Loads a `WebApplicationContext` from resource
  locations that are either Groovy scripts or XML configuration files.
* `GenericXmlContextLoader`: Loads a standard `ApplicationContext` from XML resource
  locations.
* `GenericXmlWebContextLoader`: Loads a `WebApplicationContext` from XML resource
  locations.
* `GenericPropertiesContextLoader`: Loads a standard `ApplicationContext` from Java
  properties files.


[[testcontext-bootstrapping]]
==== Bootstrapping the TestContext Framework

The default configuration for the internals of the Spring TestContext Framework is
sufficient for all common use cases. However, there are times when a development team or
third party framework would like to change the default `ContextLoader`, implement a
custom `TestContext` or `ContextCache`, augment the default sets of
`ContextCustomizerFactory` and `TestExecutionListener` implementations, and so on. For
such low-level control over how the TestContext framework operates, Spring provides a
bootstrapping strategy.

`TestContextBootstrapper` defines the SPI for bootstrapping the TestContext framework. A
`TestContextBootstrapper` is used by the `TestContextManager` to load the
`TestExecutionListener` implementations for the current test and to build the
`TestContext` that it manages. You can configure a custom bootstrapping strategy for a
test class (or test class hierarchy) by using `@BootstrapWith`, either directly or as a
meta-annotation. If a bootstrapper is not explicitly configured by using
`@BootstrapWith`, either the `DefaultTestContextBootstrapper` or the
`WebTestContextBootstrapper` is used, depending on the presence of `@WebAppConfiguration`.

Since the `TestContextBootstrapper` SPI is likely to change in the future (to accommodate
new requirements), we strongly encourage implementers not to implement this interface
directly but rather to extend `AbstractTestContextBootstrapper` or one of its concrete
subclasses instead.


[[testcontext-tel-config]]
==== `TestExecutionListener` Configuration

Spring provides the following `TestExecutionListener` implementations that are registered
by default, exactly in the following order:

* `ServletTestExecutionListener`: Configures Servlet API mocks for a
  `WebApplicationContext`.
* `DirtiesContextBeforeModesTestExecutionListener`: Handles the `@DirtiesContext`
  annotation for "`before`" modes.
* `DependencyInjectionTestExecutionListener`: Provides dependency injection for the test
  instance.
* `DirtiesContextTestExecutionListener`: Handles the `@DirtiesContext` annotation for
  "`after`" modes.
* `TransactionalTestExecutionListener`: Provides transactional test execution with
  default rollback semantics.
* `SqlScriptsTestExecutionListener`: Runs SQL scripts configured by using the `@Sql`
  annotation.
* `EventPublishingTestExecutionListener`: Publishes test execution events to the test's
  `ApplicationContext` (see <<testcontext-test-execution-events>>).

[[testcontext-tel-config-registering-tels]]
===== Registering `TestExecutionListener` Implementations

You can register `TestExecutionListener` implementations for a test class and its
subclasses by using the `@TestExecutionListeners` annotation. See
<<integration-testing-annotations, annotation support>> and the javadoc for
{api-spring-framework}/test/context/TestExecutionListeners.html[`@TestExecutionListeners`]
for details and examples.

[[testcontext-tel-config-automatic-discovery]]
===== Automatic Discovery of Default `TestExecutionListener` Implementations

Registering `TestExecutionListener` implementations by using `@TestExecutionListeners` is
suitable for custom listeners that are used in limited testing scenarios. However, it can
become cumbersome if a custom listener needs to be used across an entire test suite. This
issue is addressed through support for automatic discovery of default
`TestExecutionListener` implementations through the `SpringFactoriesLoader` mechanism.

Specifically, the `spring-test` module declares all core default `TestExecutionListener`
implementations under the `org.springframework.test.context.TestExecutionListener` key in
its `META-INF/spring.factories` properties file. Third-party frameworks and developers
can contribute their own `TestExecutionListener` implementations to the list of default
listeners in the same manner through their own `META-INF/spring.factories` properties
file.

[[testcontext-tel-config-ordering]]
===== Ordering `TestExecutionListener` Implementations

When the TestContext framework discovers default `TestExecutionListener` implementations
through the <<testcontext-tel-config-automatic-discovery, aforementioned>>
`SpringFactoriesLoader` mechanism, the instantiated listeners are sorted by using
Spring's `AnnotationAwareOrderComparator`, which honors Spring's `Ordered` interface and
`@Order` annotation for ordering. `AbstractTestExecutionListener` and all default
`TestExecutionListener` implementations provided by Spring implement `Ordered` with
appropriate values. Third-party frameworks and developers should therefore make sure that
their default `TestExecutionListener` implementations are registered in the proper order
by implementing `Ordered` or declaring `@Order`. See the javadoc for the `getOrder()`
methods of the core default `TestExecutionListener` implementations for details on what
values are assigned to each core listener.

[[testcontext-tel-config-merging]]
===== Merging `TestExecutionListener` Implementations

If a custom `TestExecutionListener` is registered via `@TestExecutionListeners`, the
default listeners are not registered. In most common testing scenarios, this effectively
forces the developer to manually declare all default listeners in addition to any custom
listeners. The following listing demonstrates this style of configuration:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@ContextConfiguration
	@TestExecutionListeners({
		MyCustomTestExecutionListener.class,
		ServletTestExecutionListener.class,
		DirtiesContextBeforeModesTestExecutionListener.class,
		DependencyInjectionTestExecutionListener.class,
		DirtiesContextTestExecutionListener.class,
		TransactionalTestExecutionListener.class,
		SqlScriptsTestExecutionListener.class
	})
	class MyTest {
		// class body...
	}
----

[source,java,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@ContextConfiguration
	@TestExecutionListeners(
		MyCustomTestExecutionListener::class,
		ServletTestExecutionListener::class,
		DirtiesContextBeforeModesTestExecutionListener::class,
		DependencyInjectionTestExecutionListener::class,
		DirtiesContextTestExecutionListener::class,
		TransactionalTestExecutionListener::class,
		SqlScriptsTestExecutionListener::class
	)
	class MyTest {
		// class body...
	}
----

The challenge with this approach is that it requires that the developer know exactly
which listeners are registered by default. Moreover, the set of default listeners can
change from release to release -- for example, `SqlScriptsTestExecutionListener` was
introduced in Spring Framework 4.1, and `DirtiesContextBeforeModesTestExecutionListener`
was introduced in Spring Framework 4.2. Furthermore, third-party frameworks like Spring
Boot and Spring Security register their own default `TestExecutionListener`
implementations by using the aforementioned <<testcontext-tel-config-automatic-discovery,
automatic discovery mechanism>>.

To avoid having to be aware of and re-declare all default listeners, you can set the
`mergeMode` attribute of `@TestExecutionListeners` to `MergeMode.MERGE_WITH_DEFAULTS`.
`MERGE_WITH_DEFAULTS` indicates that locally declared listeners should be merged with the
default listeners. The merging algorithm ensures that duplicates are removed from the
list and that the resulting set of merged listeners is sorted according to the semantics
of `AnnotationAwareOrderComparator`, as described in <<testcontext-tel-config-ordering>>.
If a listener implements `Ordered` or is annotated with `@Order`, it can influence the
position in which it is merged with the defaults. Otherwise, locally declared listeners
are appended to the list of default listeners when merged.

For example, if the `MyCustomTestExecutionListener` class in the previous example
configures its `order` value (for example, `500`) to be less than the order of the
`ServletTestExecutionListener` (which happens to be `1000`), the
`MyCustomTestExecutionListener` can then be automatically merged with the list of
defaults in front of the `ServletTestExecutionListener`, and the previous example could
be replaced with the following:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@ContextConfiguration
	@TestExecutionListeners(
		listeners = MyCustomTestExecutionListener.class,
		mergeMode = MERGE_WITH_DEFAULTS
	)
	class MyTest {
		// class body...
	}
----
[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@ContextConfiguration
	@TestExecutionListeners(
			listeners = [MyCustomTestExecutionListener::class],
			mergeMode = MERGE_WITH_DEFAULTS
	)
	class MyTest {
		// class body...
	}
----

[[testcontext-test-execution-events]]
==== Test Execution Events

The `EventPublishingTestExecutionListener` introduced in Spring Framework 5.2 offers an
alternative approach to implementing a custom `TestExecutionListener`. Components in the
test's `ApplicationContext` can listen to the following events published by the
`EventPublishingTestExecutionListener`, each of which corresponds to a method in the
`TestExecutionListener` API.

* `BeforeTestClassEvent`
* `PrepareTestInstanceEvent`
* `BeforeTestMethodEvent`
* `BeforeTestExecutionEvent`
* `AfterTestExecutionEvent`
* `AfterTestMethodEvent`
* `AfterTestClassEvent`

NOTE: These events are only published if the `ApplicationContext` has already been loaded.

These events may be consumed for various reasons, such as resetting mock beans or tracing
test execution. One advantage of consuming test execution events rather than implementing
a custom `TestExecutionListener` is that test execution events may be consumed by any
Spring bean registered in the test `ApplicationContext`, and such beans may benefit
directly from dependency injection and other features of the `ApplicationContext`. In
contrast, a `TestExecutionListener` is not a bean in the `ApplicationContext`.

In order to listen to test execution events, a Spring bean may choose to implement the
`org.springframework.context.ApplicationListener` interface. Alternatively, listener
methods can be annotated with `@EventListener` and configured to listen to one of the
particular event types listed above (see
<<core.adoc#context-functionality-events-annotation, Annotation-based Event Listeners>>).
Due to the popularity of this approach, Spring provides the following dedicated
`@EventListener` annotations to simplify registration of test execution event listeners.
These annotations reside in the `org.springframework.test.context.event.annotation`
package.

* `@BeforeTestClass`
* `@PrepareTestInstance`
* `@BeforeTestMethod`
* `@BeforeTestExecution`
* `@AfterTestExecution`
* `@AfterTestMethod`
* `@AfterTestClass`

[[testcontext-test-execution-events-exception-handling]]
===== Exception Handling

By default, if a test execution event listener throws an exception while consuming an
event, that exception will propagate to the underlying testing framework in use (such as
JUnit or TestNG). For example, if the consumption of a `BeforeTestMethodEvent` results in
an exception, the corresponding test method will fail as a result of the exception. In
contrast, if an asynchronous test execution event listener throws an exception, the
exception will not propagate to the underlying testing framework. For further details on
asynchronous exception handling, consult the class-level javadoc for `@EventListener`.

[[testcontext-test-execution-events-async]]
===== Asynchronous Listeners

If you want a particular test execution event listener to process events asynchronously,
you can use Spring's <<integration.adoc#scheduling-annotation-support-async,regular
`@Async` support>>. For further details, consult the class-level javadoc for
`@EventListener`.


[[testcontext-ctx-management]]
==== Context Management

Each `TestContext` provides context management and caching support for the test instance
for which it is responsible. Test instances do not automatically receive access to the
configured `ApplicationContext`. However, if a test class implements the
`ApplicationContextAware` interface, a reference to the `ApplicationContext` is supplied
to the test instance. Note that `AbstractJUnit4SpringContextTests` and
`AbstractTestNGSpringContextTests` implement `ApplicationContextAware` and, therefore,
provide access to the `ApplicationContext` automatically.

.@Autowired ApplicationContext
[TIP]
=====
As an alternative to implementing the `ApplicationContextAware` interface, you can inject
the application context for your test class through the `@Autowired` annotation on either
a field or setter method, as the following example shows:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@SpringJUnitConfig
	class MyTest {

		@Autowired // <1>
		ApplicationContext applicationContext;

		// class body...
	}
----
<1> Injecting the `ApplicationContext`.

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@SpringJUnitConfig
	class MyTest {

		@Autowired // <1>
		lateinit var applicationContext: ApplicationContext

		// class body...
	}
----
<1> Injecting the `ApplicationContext`.


Similarly, if your test is configured to load a `WebApplicationContext`, you can inject
the web application context into your test, as follows:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@SpringJUnitWebConfig // <1>
	class MyWebAppTest {

		@Autowired // <2>
		WebApplicationContext wac;

		// class body...
	}
----
<1> Configuring the `WebApplicationContext`.
<2> Injecting the `WebApplicationContext`.

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@SpringJUnitWebConfig // <1>
	class MyWebAppTest {

		@Autowired // <2>
		lateinit var wac: WebApplicationContext
		// class body...
	}
----
<1> Configuring the `WebApplicationContext`.
<2> Injecting the `WebApplicationContext`.


Dependency injection by using `@Autowired` is provided by the
`DependencyInjectionTestExecutionListener`, which is configured by default
(see <<testcontext-fixture-di>>).
=====

Test classes that use the TestContext framework do not need to extend any particular
class or implement a specific interface to configure their application context. Instead,
configuration is achieved by declaring the `@ContextConfiguration` annotation at the
class level. If your test class does not explicitly declare application context resource
locations or component classes, the configured `ContextLoader` determines how to load a
context from a default location or default configuration classes. In addition to context
resource locations and component classes, an application context can also be configured
through application context initializers.

The following sections explain how to use Spring's `@ContextConfiguration` annotation to
configure a test `ApplicationContext` by using XML configuration files, Groovy scripts,
component classes (typically `@Configuration` classes), or context initializers.
Alternatively, you can implement and configure your own custom `SmartContextLoader` for
advanced use cases.

* <<testcontext-ctx-management-xml>>
* <<testcontext-ctx-management-groovy>>
* <<testcontext-ctx-management-javaconfig>>
* <<testcontext-ctx-management-mixed-config>>
* <<testcontext-ctx-management-initializers>>
* <<testcontext-ctx-management-inheritance>>
* <<testcontext-ctx-management-env-profiles>>
* <<testcontext-ctx-management-property-sources>>
* <<testcontext-ctx-management-web>>
* <<testcontext-ctx-management-caching>>
* <<testcontext-ctx-management-ctx-hierarchies>>

[[testcontext-ctx-management-xml]]
===== Context Configuration with XML resources

To load an `ApplicationContext` for your tests by using XML configuration files, annotate
your test class with `@ContextConfiguration` and configure the `locations` attribute with
an array that contains the resource locations of XML configuration metadata. A plain or
relative path (for example, `context.xml`) is treated as a classpath resource that is
relative to the package in which the test class is defined. A path starting with a slash
is treated as an absolute classpath location (for example, `/org/example/config.xml`). A
path that represents a resource URL (i.e., a path prefixed with `classpath:`, `file:`,
`http:`, etc.) is used _as is_.

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@ExtendWith(SpringExtension.class)
	// ApplicationContext will be loaded from "/app-config.xml" and
	// "/test-config.xml" in the root of the classpath
	@ContextConfiguration(locations={"/app-config.xml", "/test-config.xml"}) // <1>
	class MyTest {
		// class body...
	}
----
<1> Setting the locations attribute to a list of XML files.

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@ExtendWith(SpringExtension::class)
	// ApplicationContext will be loaded from "/app-config.xml" and
	// "/test-config.xml" in the root of the classpath
	@ContextConfiguration("/app-config.xml", "/test-config.xml") // <1>
	class MyTest {
		// class body...
	}
----
<1> Setting the locations attribute to a list of XML files.


`@ContextConfiguration` supports an alias for the `locations` attribute through the
standard Java `value` attribute. Thus, if you do not need to declare additional
attributes in `@ContextConfiguration`, you can omit the declaration of the `locations`
attribute name and declare the resource locations by using the shorthand format
demonstrated in the following example:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@ExtendWith(SpringExtension.class)
	@ContextConfiguration({"/app-config.xml", "/test-config.xml"}) <1>
	class MyTest {
		// class body...
	}
----
<1> Specifying XML files without using the `location` attribute.

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@ExtendWith(SpringExtension::class)
	@ContextConfiguration("/app-config.xml", "/test-config.xml") // <1>
	class MyTest {
		// class body...
	}
----
<1> Specifying XML files without using the `location` attribute.


If you omit both the `locations` and the `value` attributes from the
`@ContextConfiguration` annotation, the TestContext framework tries to detect a default
XML resource location. Specifically, `GenericXmlContextLoader` and
`GenericXmlWebContextLoader` detect a default location based on the name of the test
class. If your class is named `com.example.MyTest`, `GenericXmlContextLoader` loads your
application context from `"classpath:com/example/MyTest-context.xml"`. The following
example shows how to do so:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@ExtendWith(SpringExtension.class)
	// ApplicationContext will be loaded from
	// "classpath:com/example/MyTest-context.xml"
	@ContextConfiguration // <1>
	class MyTest {
		// class body...
	}
----
<1> Loading configuration from the default location.

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@ExtendWith(SpringExtension::class)
	// ApplicationContext will be loaded from
	// "classpath:com/example/MyTest-context.xml"
	@ContextConfiguration // <1>
	class MyTest {
		// class body...
	}
----
<1> Loading configuration from the default location.


[[testcontext-ctx-management-groovy]]
===== Context Configuration with Groovy Scripts

To load an `ApplicationContext` for your tests by using Groovy scripts that use the
<<core.adoc#groovy-bean-definition-dsl, Groovy Bean Definition DSL>>, you can annotate
your test class with `@ContextConfiguration` and configure the `locations` or `value`
attribute with an array that contains the resource locations of Groovy scripts. Resource
lookup semantics for Groovy scripts are the same as those described for
<<testcontext-ctx-management-xml, XML configuration files>>.

.Enabling Groovy script support
TIP: Support for using Groovy scripts to load an `ApplicationContext` in the Spring
TestContext Framework is enabled automatically if Groovy is on the classpath.

The following example shows how to specify Groovy configuration files:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@ExtendWith(SpringExtension.class)
	// ApplicationContext will be loaded from "/AppConfig.groovy" and
	// "/TestConfig.groovy" in the root of the classpath
	@ContextConfiguration({"/AppConfig.groovy", "/TestConfig.Groovy"}) <1>
	class MyTest {
		// class body...
	}
----

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@ExtendWith(SpringExtension::class)
	// ApplicationContext will be loaded from "/AppConfig.groovy" and
	// "/TestConfig.groovy" in the root of the classpath
	@ContextConfiguration("/AppConfig.groovy", "/TestConfig.Groovy") // <1>
	class MyTest {
		// class body...
	}
----
<1> Specifying the location of Groovy configuration files.


If you omit both the `locations` and `value` attributes from the `@ContextConfiguration`
annotation, the TestContext framework tries to detect a default Groovy script.
Specifically, `GenericGroovyXmlContextLoader` and `GenericGroovyXmlWebContextLoader`
detect a default location based on the name of the test class. If your class is named
`com.example.MyTest`, the Groovy context loader loads your application context from
`"classpath:com/example/MyTestContext.groovy"`. The following example shows how to use
the default:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@ExtendWith(SpringExtension.class)
	// ApplicationContext will be loaded from
	// "classpath:com/example/MyTestContext.groovy"
	@ContextConfiguration // <1>
	class MyTest {
		// class body...
	}
----
<1> Loading configuration from the default location.

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@ExtendWith(SpringExtension::class)
	// ApplicationContext will be loaded from
	// "classpath:com/example/MyTestContext.groovy"
	@ContextConfiguration // <1>
	class MyTest {
		// class body...
	}
----
<1> Loading configuration from the default location.


.Declaring XML configuration and Groovy scripts simultaneously
[TIP]
=====
You can declare both XML configuration files and Groovy scripts simultaneously by using
the `locations` or `value` attribute of `@ContextConfiguration`. If the path to a
configured resource location ends with `.xml`, it is loaded by using an
`XmlBeanDefinitionReader`. Otherwise, it is loaded by using a
`GroovyBeanDefinitionReader`.

The following listing shows how to combine both in an integration test:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@ExtendWith(SpringExtension.class)
	// ApplicationContext will be loaded from
	// "/app-config.xml" and "/TestConfig.groovy"
	@ContextConfiguration({ "/app-config.xml", "/TestConfig.groovy" })
	class MyTest {
		// class body...
	}
----
[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@ExtendWith(SpringExtension::class)
	// ApplicationContext will be loaded from
	// "/app-config.xml" and "/TestConfig.groovy"
	@ContextConfiguration("/app-config.xml", "/TestConfig.groovy")
	class MyTest {
		// class body...
	}
----
=====

[[testcontext-ctx-management-javaconfig]]
===== Context Configuration with Component Classes

To load an `ApplicationContext` for your tests by using component classes (see
<<core.adoc#beans-java, Java-based container configuration>>), you can annotate your test
class with `@ContextConfiguration` and configure the `classes` attribute with an array
that contains references to component classes. The following example shows how to do so:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@ExtendWith(SpringExtension.class)
	// ApplicationContext will be loaded from AppConfig and TestConfig
	@ContextConfiguration(classes = {AppConfig.class, TestConfig.class}) // <1>
	class MyTest {
		// class body...
	}
----
<1> Specifying component classes.

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@ExtendWith(SpringExtension::class)
	// ApplicationContext will be loaded from AppConfig and TestConfig
	@ContextConfiguration(classes = [AppConfig::class, TestConfig::class]) // <1>
	class MyTest {
		// class body...
	}
----
<1> Specifying component classes.


[[testcontext-ctx-management-javaconfig-component-classes]]
.Component Classes
[TIP]
====
The term "`component class`" can refer to any of the following:

* A class annotated with `@Configuration`.
* A component (that is, a class annotated with `@Component`, `@Service`, `@Repository`, or other stereotype annotations).
* A JSR-330 compliant class that is annotated with `javax.inject` annotations.
* Any class that contains `@Bean`-methods.
* Any other class that is intended to be registered as a Spring component (i.e., a Spring
  bean in the `ApplicationContext`), potentially taking advantage of automatic autowiring
  of a single constructor without the use of Spring annotations.

See the javadoc of
{api-spring-framework}/context/annotation/Configuration.html[`@Configuration`] and
{api-spring-framework}/context/annotation/Bean.html[`@Bean`] for further information
regarding the configuration and semantics of component classes, paying special attention
to the discussion of `@Bean` Lite Mode.
====

If you omit the `classes` attribute from the `@ContextConfiguration` annotation, the
TestContext framework tries to detect the presence of default configuration classes.
Specifically, `AnnotationConfigContextLoader` and `AnnotationConfigWebContextLoader`
detect all `static` nested classes of the test class that meet the requirements for
configuration class implementations, as specified in the
{api-spring-framework}/context/annotation/Configuration.html[`@Configuration`] javadoc.
Note that the name of the configuration class is arbitrary. In addition, a test class can
contain more than one `static` nested configuration class if desired. In the following
example, the `OrderServiceTest` class declares a `static` nested configuration class
named `Config` that is automatically used to load the `ApplicationContext` for the test
class:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@SpringJUnitConfig <1>
	// ApplicationContext will be loaded from the
	// static nested Config class
	class OrderServiceTest {

		@Configuration
		static class Config {

			// this bean will be injected into the OrderServiceTest class
			@Bean
			OrderService orderService() {
				OrderService orderService = new OrderServiceImpl();
				// set properties, etc.
				return orderService;
			}
		}

		@Autowired
		OrderService orderService;

		@Test
		void testOrderService() {
			// test the orderService
		}

	}
----
<1> Loading configuration information from the nested `Config` class.

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@SpringJUnitConfig <1>
	// ApplicationContext will be loaded from the nested Config class
	class OrderServiceTest {

		@Autowired
		lateinit var orderService: OrderService

		@Configuration
		class Config {

			// this bean will be injected into the OrderServiceTest class
			@Bean
			fun orderService(): OrderService {
				// set properties, etc.
				return OrderServiceImpl()
			}
		}

		@Test
		fun testOrderService() {
			// test the orderService
		}
	}
----
<1> Loading configuration information from the nested `Config` class.


[[testcontext-ctx-management-mixed-config]]
===== Mixing XML, Groovy Scripts, and Component Classes

It may sometimes be desirable to mix XML configuration files, Groovy scripts, and
component classes (typically `@Configuration` classes) to configure an
`ApplicationContext` for your tests. For example, if you use XML configuration in
production, you may decide that you want to use `@Configuration` classes to configure
specific Spring-managed components for your tests, or vice versa.

Furthermore, some third-party frameworks (such as Spring Boot) provide first-class
support for loading an `ApplicationContext` from different types of resources
simultaneously (for example, XML configuration files, Groovy scripts, and
`@Configuration` classes). The Spring Framework, historically, has not supported this for
standard deployments. Consequently, most of the `SmartContextLoader` implementations that
the Spring Framework delivers in the `spring-test` module support only one resource type
for each test context. However, this does not mean that you cannot use both. One
exception to the general rule is that the `GenericGroovyXmlContextLoader` and
`GenericGroovyXmlWebContextLoader` support both XML configuration files and Groovy
scripts simultaneously. Furthermore, third-party frameworks may choose to support the
declaration of both `locations` and `classes` through `@ContextConfiguration`, and, with
the standard testing support in the TestContext framework, you have the following options.

If you want to use resource locations (for example, XML or Groovy) and `@Configuration`
classes to configure your tests, you must pick one as the entry point, and that one must
include or import the other. For example, in XML or Groovy scripts, you can include
`@Configuration` classes by using component scanning or defining them as normal Spring
beans, whereas, in a `@Configuration` class, you can use `@ImportResource` to import XML
configuration files or Groovy scripts. Note that this behavior is semantically equivalent
to how you configure your application in production: In production configuration, you
define either a set of XML or Groovy resource locations or a set of `@Configuration`
classes from which your production `ApplicationContext` is loaded, but you still have the
freedom to include or import the other type of configuration.

[[testcontext-ctx-management-initializers]]
===== Context Configuration with Context Initializers

To configure an `ApplicationContext` for your tests by using context initializers,
annotate your test class with `@ContextConfiguration` and configure the `initializers`
attribute with an array that contains references to classes that implement
`ApplicationContextInitializer`. The declared context initializers are then used to
initialize the `ConfigurableApplicationContext` that is loaded for your tests. Note that
the concrete `ConfigurableApplicationContext` type supported by each declared initializer
must be compatible with the type of `ApplicationContext` created by the
`SmartContextLoader` in use (typically a `GenericApplicationContext`). Furthermore, the
order in which the initializers are invoked depends on whether they implement Spring's
`Ordered` interface or are annotated with Spring's `@Order` annotation or the standard
`@Priority` annotation. The following example shows how to use initializers:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@ExtendWith(SpringExtension.class)
	// ApplicationContext will be loaded from TestConfig
	// and initialized by TestAppCtxInitializer
	@ContextConfiguration(
		classes = TestConfig.class,
		initializers = TestAppCtxInitializer.class) // <1>
	class MyTest {
		// class body...
	}
----
<1> Specifying configuration by using a configuration class and an initializer.

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@ExtendWith(SpringExtension::class)
	// ApplicationContext will be loaded from TestConfig
	// and initialized by TestAppCtxInitializer
	@ContextConfiguration(
			classes = [TestConfig::class],
			initializers = [TestAppCtxInitializer::class]) // <1>
	class MyTest {
		// class body...
	}
----
<1> Specifying configuration by using a configuration class and an initializer.


You can also omit the declaration of XML configuration files, Groovy scripts, or
component classes in `@ContextConfiguration` entirely and instead declare only
`ApplicationContextInitializer` classes, which are then responsible for registering beans
in the context -- for example, by programmatically loading bean definitions from XML
files or configuration classes. The following example shows how to do so:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@ExtendWith(SpringExtension.class)
	// ApplicationContext will be initialized by EntireAppInitializer
	// which presumably registers beans in the context
	@ContextConfiguration(initializers = EntireAppInitializer.class) <1>
	class MyTest {
		// class body...
	}
----
<1> Specifying configuration by using only an initializer.

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@ExtendWith(SpringExtension::class)
	// ApplicationContext will be initialized by EntireAppInitializer
	// which presumably registers beans in the context
	@ContextConfiguration(initializers = [EntireAppInitializer::class]) // <1>
	class MyTest {
		// class body...
	}
----
<1> Specifying configuration by using only an initializer.


[[testcontext-ctx-management-inheritance]]
===== Context Configuration Inheritance

`@ContextConfiguration` supports boolean `inheritLocations` and `inheritInitializers`
attributes that denote whether resource locations or component classes and context
initializers declared by superclasses should be inherited. The default value for both
flags is `true`. This means that a test class inherits the resource locations or
component classes as well as the context initializers declared by any superclasses.
Specifically, the resource locations or component classes for a test class are appended
to the list of resource locations or annotated classes declared by superclasses.
Similarly, the initializers for a given test class are added to the set of initializers
defined by test superclasses. Thus, subclasses have the option of extending the resource
locations, component classes, or context initializers.

If the `inheritLocations` or `inheritInitializers` attribute in `@ContextConfiguration`
is set to `false`, the resource locations or component classes and the context
initializers, respectively, for the test class shadow and effectively replace the
configuration defined by superclasses.

In the next example, which uses XML resource locations, the `ApplicationContext` for
`ExtendedTest` is loaded from `base-config.xml` and `extended-config.xml`, in that order.
Beans defined in `extended-config.xml` can, therefore, override (that is, replace) those
defined in `base-config.xml`. The following example shows how one class can extend
another and use both its own configuration file and the superclass's configuration file:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@ExtendWith(SpringExtension.class)
	// ApplicationContext will be loaded from "/base-config.xml"
	// in the root of the classpath
	@ContextConfiguration("/base-config.xml") <1>
	class BaseTest {
		// class body...
	}

	// ApplicationContext will be loaded from "/base-config.xml" and
	// "/extended-config.xml" in the root of the classpath
	@ContextConfiguration("/extended-config.xml") <2>
	class ExtendedTest extends BaseTest {
		// class body...
	}
----
<1> Configuration file defined in the superclass.
<2> Configuration file defined in the subclass.

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@ExtendWith(SpringExtension::class)
	// ApplicationContext will be loaded from "/base-config.xml"
	// in the root of the classpath
	@ContextConfiguration("/base-config.xml") // <1>
	open class BaseTest {
		// class body...
	}

	// ApplicationContext will be loaded from "/base-config.xml" and
	// "/extended-config.xml" in the root of the classpath
	@ContextConfiguration("/extended-config.xml") // <2>
	class ExtendedTest : BaseTest() {
		// class body...
	}
----
<1> Configuration file defined in the superclass.
<2> Configuration file defined in the subclass.


Similarly, in the next example, which uses component classes, the `ApplicationContext`
for `ExtendedTest` is loaded from the `BaseConfig` and `ExtendedConfig` classes, in that
order. Beans defined in `ExtendedConfig` can, therefore, override (that is, replace)
those defined in `BaseConfig`. The following example shows how one class can extend
another and use both its own configuration class and the superclass's configuration class:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	// ApplicationContext will be loaded from BaseConfig
	@SpringJUnitConfig(BaseConfig.class) // <1>
	class BaseTest {
		// class body...
	}

	// ApplicationContext will be loaded from BaseConfig and ExtendedConfig
	@SpringJUnitConfig(ExtendedConfig.class) // <2>
	class ExtendedTest extends BaseTest {
		// class body...
	}
----
<1> Configuration class defined in the superclass.
<2> Configuration class defined in the subclass.

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	// ApplicationContext will be loaded from BaseConfig
	@SpringJUnitConfig(BaseConfig::class) // <1>
	open class BaseTest {
		// class body...
	}

	// ApplicationContext will be loaded from BaseConfig and ExtendedConfig
	@SpringJUnitConfig(ExtendedConfig::class) // <2>
	class ExtendedTest : BaseTest() {
		// class body...
	}
----
<1> Configuration class defined in the superclass.
<2> Configuration class defined in the subclass.


In the next example, which uses context initializers, the `ApplicationContext` for
`ExtendedTest` is initialized by using `BaseInitializer` and `ExtendedInitializer`. Note,
however, that the order in which the initializers are invoked depends on whether they
implement Spring's `Ordered` interface or are annotated with Spring's `@Order` annotation
or the standard `@Priority` annotation. The following example shows how one class can
extend another and use both its own initializer and the superclass's initializer:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	// ApplicationContext will be initialized by BaseInitializer
	@SpringJUnitConfig(initializers = BaseInitializer.class) // <1>
	class BaseTest {
		// class body...
	}

	// ApplicationContext will be initialized by BaseInitializer
	// and ExtendedInitializer
	@SpringJUnitConfig(initializers = ExtendedInitializer.class) // <2>
	class ExtendedTest extends BaseTest {
		// class body...
	}
----
<1> Initializer defined in the superclass.
<2> Initializer defined in the subclass.

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	// ApplicationContext will be initialized by BaseInitializer
	@SpringJUnitConfig(initializers = [BaseInitializer::class]) // <1>
	open class BaseTest {
		// class body...
	}

	// ApplicationContext will be initialized by BaseInitializer
	// and ExtendedInitializer
	@SpringJUnitConfig(initializers = [ExtendedInitializer::class]) // <2>
	class ExtendedTest : BaseTest() {
		// class body...
	}
----
<1> Initializer defined in the superclass.
<2> Initializer defined in the subclass.


[[testcontext-ctx-management-env-profiles]]
===== Context Configuration with Environment Profiles

The Spring Framework has first-class support for the notion of environments and profiles
(AKA "bean definition profiles"), and integration tests can be configured to activate
particular bean definition profiles for various testing scenarios. This is achieved by
annotating a test class with the `@ActiveProfiles` annotation and supplying a list of
profiles that should be activated when loading the `ApplicationContext` for the test.

NOTE: You can use `@ActiveProfiles` with any implementation of the `SmartContextLoader`
SPI, but `@ActiveProfiles` is not supported with implementations of the older
`ContextLoader` SPI.

Consider two examples with XML configuration and `@Configuration` classes:

[source,xml,indent=0,subs="verbatim,quotes"]
----
	<!-- app-config.xml -->
	<beans xmlns="http://www.springframework.org/schema/beans"
		xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
		xmlns:jdbc="http://www.springframework.org/schema/jdbc"
		xmlns:jee="http://www.springframework.org/schema/jee"
		xsi:schemaLocation="...">

		<bean id="transferService"
				class="com.bank.service.internal.DefaultTransferService">
			<constructor-arg ref="accountRepository"/>
			<constructor-arg ref="feePolicy"/>
		</bean>

		<bean id="accountRepository"
				class="com.bank.repository.internal.JdbcAccountRepository">
			<constructor-arg ref="dataSource"/>
		</bean>

		<bean id="feePolicy"
			class="com.bank.service.internal.ZeroFeePolicy"/>

		<beans profile="dev">
			<jdbc:embedded-database id="dataSource">
				<jdbc:script
					location="classpath:com/bank/config/sql/schema.sql"/>
				<jdbc:script
					location="classpath:com/bank/config/sql/test-data.sql"/>
			</jdbc:embedded-database>
		</beans>

		<beans profile="production">
			<jee:jndi-lookup id="dataSource" jndi-name="java:comp/env/jdbc/datasource"/>
		</beans>

		<beans profile="default">
			<jdbc:embedded-database id="dataSource">
				<jdbc:script
					location="classpath:com/bank/config/sql/schema.sql"/>
			</jdbc:embedded-database>
		</beans>

	</beans>
----

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@ExtendWith(SpringExtension.class)
	// ApplicationContext will be loaded from "classpath:/app-config.xml"
	@ContextConfiguration("/app-config.xml")
	@ActiveProfiles("dev")
	class TransferServiceTest {

		@Autowired
		TransferService transferService;

		@Test
		void testTransferService() {
			// test the transferService
		}
	}
----
[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@ExtendWith(SpringExtension::class)
	// ApplicationContext will be loaded from "classpath:/app-config.xml"
	@ContextConfiguration("/app-config.xml")
	@ActiveProfiles("dev")
	class TransferServiceTest {

		@Autowired
		lateinit var transferService: TransferService

		@Test
		fun testTransferService() {
			// test the transferService
		}
	}
----

When `TransferServiceTest` is run, its `ApplicationContext` is loaded from the
`app-config.xml` configuration file in the root of the classpath. If you inspect
`app-config.xml`, you can see that the `accountRepository` bean has a dependency on a
`dataSource` bean. However, `dataSource` is not defined as a top-level bean. Instead,
`dataSource` is defined three times: in the `production` profile, in the `dev` profile,
and in the `default` profile.

By annotating `TransferServiceTest` with `@ActiveProfiles("dev")`, we instruct the Spring
TestContext Framework to load the `ApplicationContext` with the active profiles set to
`{"dev"}`. As a result, an embedded database is created and populated with test data, and
the `accountRepository` bean is wired with a reference to the development `DataSource`.
That is likely what we want in an integration test.

It is sometimes useful to assign beans to a `default` profile. Beans within the default
profile are included only when no other profile is specifically activated. You can use
this to define "`fallback`" beans to be used in the application's default state. For
example, you may explicitly provide a data source for `dev` and `production` profiles,
but define an in-memory data source as a default when neither of these is active.

The following code listings demonstrate how to implement the same configuration and
integration test with `@Configuration` classes instead of XML:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@Configuration
	@Profile("dev")
	public class StandaloneDataConfig {

		@Bean
		public DataSource dataSource() {
			return new EmbeddedDatabaseBuilder()
				.setType(EmbeddedDatabaseType.HSQL)
				.addScript("classpath:com/bank/config/sql/schema.sql")
				.addScript("classpath:com/bank/config/sql/test-data.sql")
				.build();
		}
	}
----
[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@Configuration
	@Profile("dev")
	class StandaloneDataConfig {

		@Bean
		fun dataSource(): DataSource {
			return EmbeddedDatabaseBuilder()
					.setType(EmbeddedDatabaseType.HSQL)
					.addScript("classpath:com/bank/config/sql/schema.sql")
					.addScript("classpath:com/bank/config/sql/test-data.sql")
					.build()
		}
	}
----

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@Configuration
	@Profile("production")
	public class JndiDataConfig {

		@Bean(destroyMethod="")
		public DataSource dataSource() throws Exception {
			Context ctx = new InitialContext();
			return (DataSource) ctx.lookup("java:comp/env/jdbc/datasource");
		}
	}
----
[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@Configuration
	@Profile("production")
	class JndiDataConfig {

		@Bean(destroyMethod = "")
		fun dataSource(): DataSource {
			val ctx = InitialContext()
			return ctx.lookup("java:comp/env/jdbc/datasource") as DataSource
		}
	}
----

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@Configuration
	@Profile("default")
	public class DefaultDataConfig {

		@Bean
		public DataSource dataSource() {
			return new EmbeddedDatabaseBuilder()
				.setType(EmbeddedDatabaseType.HSQL)
				.addScript("classpath:com/bank/config/sql/schema.sql")
				.build();
		}
	}
----
[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@Configuration
	@Profile("default")
	class DefaultDataConfig {

		@Bean
		fun dataSource(): DataSource {
			return EmbeddedDatabaseBuilder()
					.setType(EmbeddedDatabaseType.HSQL)
					.addScript("classpath:com/bank/config/sql/schema.sql")
					.build()
		}
	}
----

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@Configuration
	public class TransferServiceConfig {

		@Autowired DataSource dataSource;

		@Bean
		public TransferService transferService() {
			return new DefaultTransferService(accountRepository(), feePolicy());
		}

		@Bean
		public AccountRepository accountRepository() {
			return new JdbcAccountRepository(dataSource);
		}

		@Bean
		public FeePolicy feePolicy() {
			return new ZeroFeePolicy();
		}
	}
----
[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@Configuration
	class TransferServiceConfig {

		@Autowired
		lateinit var dataSource: DataSource

		@Bean
		fun transferService(): TransferService {
			return DefaultTransferService(accountRepository(), feePolicy())
		}

		@Bean
		fun accountRepository(): AccountRepository {
			return JdbcAccountRepository(dataSource)
		}

		@Bean
		fun feePolicy(): FeePolicy {
			return ZeroFeePolicy()
		}
	}
----

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@SpringJUnitConfig({
			TransferServiceConfig.class,
			StandaloneDataConfig.class,
			JndiDataConfig.class,
			DefaultDataConfig.class})
	@ActiveProfiles("dev")
	class TransferServiceTest {

		@Autowired
		TransferService transferService;

		@Test
		void testTransferService() {
			// test the transferService
		}
	}
----
[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@SpringJUnitConfig(
			TransferServiceConfig::class,
			StandaloneDataConfig::class,
			JndiDataConfig::class,
			DefaultDataConfig::class)
	@ActiveProfiles("dev")
	class TransferServiceTest {

		@Autowired
		lateinit var transferService: TransferService

		@Test
		fun testTransferService() {
			// test the transferService
		}
	}
----

In this variation, we have split the XML configuration into four independent
`@Configuration` classes:

* `TransferServiceConfig`: Acquires a `dataSource` through dependency injection by using
  `@Autowired`.
* `StandaloneDataConfig`: Defines a `dataSource` for an embedded database suitable for
  developer tests.
* `JndiDataConfig`: Defines a `dataSource` that is retrieved from JNDI in a production
  environment.
* `DefaultDataConfig`: Defines a `dataSource` for a default embedded database, in case no
  profile is active.

As with the XML-based configuration example, we still annotate `TransferServiceTest` with
`@ActiveProfiles("dev")`, but this time we specify all four configuration classes by
using the `@ContextConfiguration` annotation. The body of the test class itself remains
completely unchanged.

It is often the case that a single set of profiles is used across multiple test classes
within a given project. Thus, to avoid duplicate declarations of the `@ActiveProfiles`
annotation, you can declare `@ActiveProfiles` once on a base class, and subclasses
automatically inherit the `@ActiveProfiles` configuration from the base class. In the
following example, the declaration of `@ActiveProfiles` (as well as other annotations)
has been moved to an abstract superclass, `AbstractIntegrationTest`:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@SpringJUnitConfig({
			TransferServiceConfig.class,
			StandaloneDataConfig.class,
			JndiDataConfig.class,
			DefaultDataConfig.class})
	@ActiveProfiles("dev")
	abstract class AbstractIntegrationTest {
	}
----

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@SpringJUnitConfig(
			TransferServiceConfig::class,
			StandaloneDataConfig::class,
			JndiDataConfig::class,
			DefaultDataConfig::class)
	@ActiveProfiles("dev")
	abstract class AbstractIntegrationTest {
	}
----

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	// "dev" profile inherited from superclass
	class TransferServiceTest extends AbstractIntegrationTest {

		@Autowired
		TransferService transferService;

		@Test
		void testTransferService() {
			// test the transferService
		}
	}
----
[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	// "dev" profile inherited from superclass
	class TransferServiceTest : AbstractIntegrationTest() {

		@Autowired
		lateinit var transferService: TransferService

		@Test
		fun testTransferService() {
			// test the transferService
		}
	}
----

`@ActiveProfiles` also supports an `inheritProfiles` attribute that can be used to
disable the inheritance of active profiles, as the following example shows:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	// "dev" profile overridden with "production"
	@ActiveProfiles(profiles = "production", inheritProfiles = false)
	class ProductionTransferServiceTest extends AbstractIntegrationTest {
		// test body
	}
----

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	// "dev" profile overridden with "production"
	@ActiveProfiles("production", inheritProfiles = false)
	class ProductionTransferServiceTest : AbstractIntegrationTest() {
		// test body
	}
----

[[testcontext-ctx-management-env-profiles-ActiveProfilesResolver]]
Furthermore, it is sometimes necessary to resolve active profiles for tests
programmatically instead of declaratively -- for example, based on:

* The current operating system.
* Whether tests are being executed on a continuous integration build server.
* The presence of certain environment variables.
* The presence of custom class-level annotations.
* Other concerns.

To resolve active bean definition profiles programmatically, you can implement
a custom `ActiveProfilesResolver` and register it by using the `resolver`
attribute of `@ActiveProfiles`. For further information, see the corresponding
{api-spring-framework}/test/context/ActiveProfilesResolver.html[javadoc].
The following example demonstrates how to implement and register a custom
`OperatingSystemActiveProfilesResolver`:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	// "dev" profile overridden programmatically via a custom resolver
	@ActiveProfiles(
			resolver = OperatingSystemActiveProfilesResolver.class,
			inheritProfiles = false)
	class TransferServiceTest extends AbstractIntegrationTest {
		// test body
	}
----

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	// "dev" profile overridden programmatically via a custom resolver
	@ActiveProfiles(
			resolver = OperatingSystemActiveProfilesResolver::class,
			inheritProfiles = false)
	class TransferServiceTest : AbstractIntegrationTest() {
		// test body
	}
----

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	public class OperatingSystemActiveProfilesResolver implements ActiveProfilesResolver {

		@Override
		public String[] resolve(Class<?> testClass) {
			String profile = ...;
			// determine the value of profile based on the operating system
			return new String[] {profile};
		}
	}
----
[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	class OperatingSystemActiveProfilesResolver : ActiveProfilesResolver {

		override fun resolve(testClass: Class<*>): Array<String> {
			val profile: String = ...
			// determine the value of profile based on the operating system
			return arrayOf(profile)
		}
	}
----

[[testcontext-ctx-management-property-sources]]
===== Context Configuration with Test Property Sources

The Spring Framework has first-class support for the notion of an environment with a
hierarchy of property sources, and you can configure integration tests with test-specific
property sources. In contrast to the `@PropertySource` annotation used on
`@Configuration` classes, you can declare the `@TestPropertySource` annotation on a test
class to declare resource locations for test properties files or inlined properties.
These test property sources are added to the set of `PropertySources` in the
`Environment` for the `ApplicationContext` loaded for the annotated integration test.

[NOTE]
====
You can use `@TestPropertySource` with any implementation of the `SmartContextLoader`
SPI, but `@TestPropertySource` is not supported with implementations of the older
`ContextLoader` SPI.

Implementations of `SmartContextLoader` gain access to merged test property source values
through the `getPropertySourceLocations()` and `getPropertySourceProperties()` methods in
`MergedContextConfiguration`.
====

====== Declaring Test Property Sources

You can configure test properties files by using the `locations` or `value` attribute of
`@TestPropertySource`.

Both traditional and XML-based properties file formats are supported -- for example,
`"classpath:/com/example/test.properties"` or `"file:///path/to/file.xml"`.

Each path is interpreted as a Spring `Resource`. A plain path (for example,
`"test.properties"`) is treated as a classpath resource that is relative to the package
in which the test class is defined. A path starting with a slash is treated as an
absolute classpath resource (for example: `"/org/example/test.xml"`). A path that
references a URL (for example, a path prefixed with `classpath:`, `file:`, or `http:`) is
loaded by using the specified resource protocol. Resource location wildcards (such as
`**/*.properties`) are not permitted: Each location must evaluate to exactly one
`.properties` or `.xml` resource.

The following example uses a test properties file:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@ContextConfiguration
	@TestPropertySource("/test.properties") // <1>
	class MyIntegrationTests {
		// class body...
	}
----
<1> Specifying a properties file with an absolute path.

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@ContextConfiguration
	@TestPropertySource("/test.properties") // <1>
	class MyIntegrationTests {
		// class body...
	}
----
<1> Specifying a properties file with an absolute path.


You can configure inlined properties in the form of key-value pairs by using the
`properties` attribute of `@TestPropertySource`, as shown in the next example. All
key-value pairs are added to the enclosing `Environment` as a single test
`PropertySource` with the highest precedence.

The supported syntax for key-value pairs is the same as the syntax defined for entries in
a Java properties file:

* `key=value`
* `key:value`
* `key value`

The following example sets two inlined properties:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@ContextConfiguration
	@TestPropertySource(properties = {"timezone = GMT", "port: 4242"}) // <1>
	class MyIntegrationTests {
		// class body...
	}
----
<1> Setting two properties by using two variations of the key-value syntax.

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@ContextConfiguration
	@TestPropertySource(properties = ["timezone = GMT", "port: 4242"]) // <1>
	class MyIntegrationTests {
		// class body...
	}
----
<1> Setting two properties by using two variations of the key-value syntax.

[NOTE]
====
As of Spring Framework 5.2, `@TestPropertySource` can be used as _repeatable annotation_.
That means that you can have multiple declarations of `@TestPropertySource` on a single
test class, with the `locations` and `properties` from later `@TestPropertySource`
annotations overriding those from previous `@TestPropertySource` annotations.

In addition, you may declare multiple composed annotations on a test class that are each
meta-annotated with `@TestPropertySource`, and all of those `@TestPropertySource`
declarations will contribute to your test property sources.

Directly present `@TestPropertySource` annotations always take precedence over
meta-present `@TestPropertySource` annotations. In other words, `locations` and
`properties` from a directly present `@TestPropertySource` annotation will override the
`locations` and `properties` from a `@TestPropertySource` annotation used as a
meta-annotation.
====


====== Default Properties File Detection

If `@TestPropertySource` is declared as an empty annotation (that is, without explicit
values for the `locations` or `properties` attributes), an attempt is made to detect a
default properties file relative to the class that declared the annotation. For example,
if the annotated test class is `com.example.MyTest`, the corresponding default properties
file is `classpath:com/example/MyTest.properties`. If the default cannot be detected, an
`IllegalStateException` is thrown.

====== Precedence

Test property sources have higher precedence than those loaded from the operating
system's environment, Java system properties, or property sources added by the
application declaratively by using `@PropertySource` or programmatically. Thus, test
property sources can be used to selectively override properties defined in system and
application property sources. Furthermore, inlined properties have higher precedence than
properties loaded from resource locations.

In the next example, the `timezone` and `port` properties and any properties defined in
`"/test.properties"` override any properties of the same name that are defined in system
and application property sources. Furthermore, if the `"/test.properties"` file defines
entries for the `timezone` and `port` properties those are overridden by the inlined
properties declared by using the `properties` attribute. The following example shows how
to specify properties both in a file and inline:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@ContextConfiguration
	@TestPropertySource(
		locations = "/test.properties",
		properties = {"timezone = GMT", "port: 4242"}
	)
	class MyIntegrationTests {
		// class body...
	}
----

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@ContextConfiguration
	@TestPropertySource("/test.properties",
			properties = ["timezone = GMT", "port: 4242"]
	)
	class MyIntegrationTests {
		// class body...
	}
----

====== Inheriting and Overriding Test Property Sources

`@TestPropertySource` supports boolean `inheritLocations` and `inheritProperties`
attributes that denote whether resource locations for properties files and inlined
properties declared by superclasses should be inherited. The default value for both flags
is `true`. This means that a test class inherits the locations and inlined properties
declared by any superclasses. Specifically, the locations and inlined properties for a
test class are appended to the locations and inlined properties declared by superclasses.
Thus, subclasses have the option of extending the locations and inlined properties. Note
that properties that appear later shadow (that is, override) properties of the same name
that appear earlier. In addition, the aforementioned precedence rules apply for inherited
test property sources as well.

If the `inheritLocations` or `inheritProperties` attribute in `@TestPropertySource` is
set to `false`, the locations or inlined properties, respectively, for the test class
shadow and effectively replace the configuration defined by superclasses.

In the next example, the `ApplicationContext` for `BaseTest` is loaded by using only the
`base.properties` file as a test property source. In contrast, the `ApplicationContext`
for `ExtendedTest` is loaded by using the `base.properties` and `extended.properties`
files as test property source locations. The following example shows how to define
properties in both a subclass and its superclass by using `properties` files:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@TestPropertySource("base.properties")
	@ContextConfiguration
	class BaseTest {
		// ...
	}

	@TestPropertySource("extended.properties")
	@ContextConfiguration
	class ExtendedTest extends BaseTest {
		// ...
	}
----
[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@TestPropertySource("base.properties")
	@ContextConfiguration
	open class BaseTest {
		// ...
	}

	@TestPropertySource("extended.properties")
	@ContextConfiguration
	class ExtendedTest : BaseTest() {
		// ...
	}
----

In the next example, the `ApplicationContext` for `BaseTest` is loaded by using only the
inlined `key1` property. In contrast, the `ApplicationContext` for `ExtendedTest` is
loaded by using the inlined `key1` and `key2` properties. The following example shows how
to define properties in both a subclass and its superclass by using inline properties:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@TestPropertySource(properties = "key1 = value1")
	@ContextConfiguration
	class BaseTest {
		// ...
	}

	@TestPropertySource(properties = "key2 = value2")
	@ContextConfiguration
	class ExtendedTest extends BaseTest {
		// ...
	}
----

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@TestPropertySource(properties = ["key1 = value1"])
	@ContextConfiguration
	open class BaseTest {
		// ...
	}

	@TestPropertySource(properties = ["key2 = value2"])
	@ContextConfiguration
	class ExtendedTest : BaseTest() {
		// ...
	}
----

[[testcontext-ctx-management-web]]
===== Loading a `WebApplicationContext`

To instruct the TestContext framework to load a `WebApplicationContext` instead of a
standard `ApplicationContext`, you can annotate the respective test class with
`@WebAppConfiguration`.

The presence of `@WebAppConfiguration` on your test class instructs the TestContext
framework (TCF) that a `WebApplicationContext` (WAC) should be loaded for your
integration tests. In the background, the TCF makes sure that a `MockServletContext` is
created and supplied to your test's WAC. By default, the base resource path for your
`MockServletContext` is set to `src/main/webapp`. This is interpreted as a path relative
to the root of your JVM (normally the path to your project). If you are familiar with the
directory structure of a web application in a Maven project, you know that
`src/main/webapp` is the default location for the root of your WAR. If you need to
override this default, you can provide an alternate path to the `@WebAppConfiguration`
annotation (for example, `@WebAppConfiguration("src/test/webapp")`). If you wish to
reference a base resource path from the classpath instead of the file system, you can use
Spring's `classpath:` prefix.

Note that Spring's testing support for `WebApplicationContext` implementations is on par
with its support for standard `ApplicationContext` implementations. When testing with a
`WebApplicationContext`, you are free to declare XML configuration files, Groovy scripts,
or `@Configuration` classes by using `@ContextConfiguration`. You are also free to use
any other test annotations, such as `@ActiveProfiles`, `@TestExecutionListeners`, `@Sql`,
`@Rollback`, and others.

The remaining examples in this section show some of the various configuration options for
loading a `WebApplicationContext`. The following example shows the TestContext
framework's support for convention over configuration:

.Conventions
[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@ExtendWith(SpringExtension.class)

	// defaults to "file:src/main/webapp"
	@WebAppConfiguration

	// detects "WacTests-context.xml" in the same package
	// or static nested @Configuration classes
	@ContextConfiguration
	class WacTests {
		//...
	}
----
[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@ExtendWith(SpringExtension::class)

	// defaults to "file:src/main/webapp"
	@WebAppConfiguration

	// detects "WacTests-context.xml" in the same package
	// or static nested @Configuration classes
	@ContextConfiguration
	class WacTests {
		//...
	}
----

If you annotate a test class with `@WebAppConfiguration` without specifying a resource
base path, the resource path effectively defaults to `file:src/main/webapp`. Similarly,
if you declare `@ContextConfiguration` without specifying resource `locations`, component
`classes`, or context `initializers`, Spring tries to detect the presence of your
configuration by using conventions (that is, `WacTests-context.xml` in the same package
as the `WacTests` class or static nested `@Configuration` classes).

The following example shows how to explicitly declare a resource base path with
`@WebAppConfiguration` and an XML resource location with `@ContextConfiguration`:

.Default resource semantics
[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@ExtendWith(SpringExtension.class)

	// file system resource
	@WebAppConfiguration("webapp")

	// classpath resource
	@ContextConfiguration("/spring/test-servlet-config.xml")
	class WacTests {
		//...
	}
----
[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@ExtendWith(SpringExtension::class)

	// file system resource
	@WebAppConfiguration("webapp")

	// classpath resource
	@ContextConfiguration("/spring/test-servlet-config.xml")
	class WacTests {
		//...
	}
----

The important thing to note here is the different semantics for paths with these two
annotations. By default, `@WebAppConfiguration` resource paths are file system based,
whereas `@ContextConfiguration` resource locations are classpath based.

The following example shows that we can override the default resource semantics for both
annotations by specifying a Spring resource prefix:

.Explicit resource semantics
[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@ExtendWith(SpringExtension.class)

	// classpath resource
	@WebAppConfiguration("classpath:test-web-resources")

	// file system resource
	@ContextConfiguration("file:src/main/webapp/WEB-INF/servlet-config.xml")
	class WacTests {
		//...
	}
----
[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@ExtendWith(SpringExtension::class)

	// classpath resource
	@WebAppConfiguration("classpath:test-web-resources")

	// file system resource
	@ContextConfiguration("file:src/main/webapp/WEB-INF/servlet-config.xml")
	class WacTests {
		//...
	}
----

Contrast the comments in this example with the previous example.

.[[testcontext-ctx-management-web-mocks]]Working with Web Mocks
--
To provide comprehensive web testing support, the TestContext framework has a
`ServletTestExecutionListener` that is enabled by default. When testing against a
`WebApplicationContext`, this <<testcontext-key-abstractions, `TestExecutionListener`>>
sets up default thread-local state by using Spring Web's `RequestContextHolder` before
each test method and creates a `MockHttpServletRequest`, a `MockHttpServletResponse`, and
a `ServletWebRequest` based on the base resource path configured with
`@WebAppConfiguration`. `ServletTestExecutionListener` also ensures that the
`MockHttpServletResponse` and `ServletWebRequest` can be injected into the test instance,
and, once the test is complete, it cleans up thread-local state.

Once you have a `WebApplicationContext` loaded for your test, you might find that you
need to interact with the web mocks -- for example, to set up your test fixture or to
perform assertions after invoking your web component. The following example shows which
mocks can be autowired into your test instance. Note that the `WebApplicationContext` and
`MockServletContext` are both cached across the test suite, whereas the other mocks are
managed per test method by the `ServletTestExecutionListener`.

.Injecting mocks
[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@SpringJUnitWebConfig
	class WacTests {

		@Autowired
		WebApplicationContext wac; // cached

		@Autowired
		MockServletContext servletContext; // cached

		@Autowired
		MockHttpSession session;

		@Autowired
		MockHttpServletRequest request;

		@Autowired
		MockHttpServletResponse response;

		@Autowired
		ServletWebRequest webRequest;

		//...
	}
----

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@SpringJUnitWebConfig
	class WacTests {

		@Autowired
		lateinit var wac: WebApplicationContext // cached

		@Autowired
		lateinit var servletContext: MockServletContext // cached

		@Autowired
		lateinit var session: MockHttpSession

		@Autowired
		lateinit var request: MockHttpServletRequest

		@Autowired
		lateinit var response: MockHttpServletResponse

		@Autowired
		lateinit var webRequest: ServletWebRequest

		//...
	}
----
--

[[testcontext-ctx-management-caching]]
===== Context Caching

Once the TestContext framework loads an `ApplicationContext` (or `WebApplicationContext`)
for a test, that context is cached and reused for all subsequent tests that declare the
same unique context configuration within the same test suite. To understand how caching
works, it is important to understand what is meant by "`unique`" and "`test suite.`"

An `ApplicationContext` can be uniquely identified by the combination of configuration
parameters that is used to load it. Consequently, the unique combination of configuration
parameters is used to generate a key under which the context is cached. The TestContext
framework uses the following configuration parameters to build the context cache key:

* `locations` (from `@ContextConfiguration`)
* `classes` (from `@ContextConfiguration`)
* `contextInitializerClasses` (from `@ContextConfiguration`)
* `contextCustomizers` (from `ContextCustomizerFactory`)
* `contextLoader` (from `@ContextConfiguration`)
* `parent` (from `@ContextHierarchy`)
* `activeProfiles` (from `@ActiveProfiles`)
* `propertySourceLocations` (from `@TestPropertySource`)
* `propertySourceProperties` (from `@TestPropertySource`)
* `resourceBasePath` (from `@WebAppConfiguration`)

For example, if `TestClassA` specifies `{"app-config.xml", "test-config.xml"}` for the
`locations` (or `value`) attribute of `@ContextConfiguration`, the TestContext framework
loads the corresponding `ApplicationContext` and stores it in a `static` context cache
under a key that is based solely on those locations. So, if `TestClassB` also defines
`{"app-config.xml", "test-config.xml"}` for its locations (either explicitly or
implicitly through inheritance) but does not define `@WebAppConfiguration`, a different
`ContextLoader`, different active profiles, different context initializers, different
test property sources, or a different parent context, then the same `ApplicationContext`
is shared by both test classes. This means that the setup cost for loading an application
context is incurred only once (per test suite), and subsequent test execution is much
faster.

.Test suites and forked processes
[NOTE]
====
The Spring TestContext framework stores application contexts in a static cache. This
means that the context is literally stored in a `static` variable. In other words, if
tests execute in separate processes, the static cache is cleared between each test
execution, which effectively disables the caching mechanism.

To benefit from the caching mechanism, all tests must run within the same process or test
suite. This can be achieved by executing all tests as a group within an IDE. Similarly,
when executing tests with a build framework such as Ant, Maven, or Gradle, it is
important to make sure that the build framework does not fork between tests. For example,
if the
https://maven.apache.org/plugins/maven-surefire-plugin/test-mojo.html#forkMode[`forkMode`]
for the Maven Surefire plug-in is set to `always` or `pertest`, the TestContext framework
cannot cache application contexts between test classes, and the build process runs
significantly more slowly as a result.
====

The size of the context cache is bounded with a default maximum size of 32. Whenever the
maximum size is reached, a least recently used (LRU) eviction policy is used to evict and
close stale contexts. You can configure the maximum size from the command line or a build
script by setting a JVM system property named `spring.test.context.cache.maxSize`. As an
alternative, you can set the same property programmatically by using the
`SpringProperties` API.

Since having a large number of application contexts loaded within a given test suite can
cause the suite to take an unnecessarily long time to execute, it is often beneficial to
know exactly how many contexts have been loaded and cached. To view the statistics for
the underlying context cache, you can set the log level for the
`org.springframework.test.context.cache` logging category to `DEBUG`.

In the unlikely case that a test corrupts the application context and requires reloading
(for example, by modifying a bean definition or the state of an application object), you
can annotate your test class or test method with `@DirtiesContext` (see the discussion of
`@DirtiesContext` in <<spring-testing-annotation-dirtiescontext>>). This instructs Spring
to remove the context from the cache and rebuild the application context before running
the next test that requires the same application context. Note that support for the
`@DirtiesContext` annotation is provided by the
`DirtiesContextBeforeModesTestExecutionListener` and the
`DirtiesContextTestExecutionListener`, which are enabled by default.

[[testcontext-ctx-management-ctx-hierarchies]]
===== Context Hierarchies

When writing integration tests that rely on a loaded Spring `ApplicationContext`, it is
often sufficient to test against a single context. However, there are times when it is
beneficial or even necessary to test against a hierarchy of `ApplicationContext`
instances. For example, if you are developing a Spring MVC web application, you typically
have a root `WebApplicationContext` loaded by Spring's `ContextLoaderListener` and a
child `WebApplicationContext` loaded by Spring's `DispatcherServlet`. This results in a
parent-child context hierarchy where shared components and infrastructure configuration
are declared in the root context and consumed in the child context by web-specific
components. Another use case can be found in Spring Batch applications, where you often
have a parent context that provides configuration for shared batch infrastructure and a
child context for the configuration of a specific batch job.

You can write integration tests that use context hierarchies by declaring context
configuration with the `@ContextHierarchy` annotation, either on an individual test class
or within a test class hierarchy. If a context hierarchy is declared on multiple classes
within a test class hierarchy, you can also merge or override the context configuration
for a specific, named level in the context hierarchy. When merging configuration for a
given level in the hierarchy, the configuration resource type (that is, XML configuration
files or component classes) must be consistent. Otherwise, it is perfectly acceptable to
have different levels in a context hierarchy configured using different resource types.

The remaining JUnit Jupiter based examples in this section show common configuration
scenarios for integration tests that require the use of context hierarchies.

.Single test class with context hierarchy
--
`ControllerIntegrationTests` represents a typical integration testing scenario for a
Spring MVC web application by declaring a context hierarchy that consists of two levels,
one for the root `WebApplicationContext` (loaded by using the `TestAppConfig`
`@Configuration` class) and one for the dispatcher servlet `WebApplicationContext`
(loaded by using the `WebConfig` `@Configuration` class). The `WebApplicationContext`
that is autowired into the test instance is the one for the child context (that is, the
lowest context in the hierarchy). The following listing shows this configuration scenario:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@ExtendWith(SpringExtension.class)
	@WebAppConfiguration
	@ContextHierarchy({
		@ContextConfiguration(classes = TestAppConfig.class),
		@ContextConfiguration(classes = WebConfig.class)
	})
	class ControllerIntegrationTests {

		@Autowired
		WebApplicationContext wac;

		// ...
	}
----

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@ExtendWith(SpringExtension::class)
	@WebAppConfiguration
	@ContextHierarchy(
		ContextConfiguration(classes = [TestAppConfig::class]),
		ContextConfiguration(classes = [WebConfig::class]))
	class ControllerIntegrationTests {

		@Autowired
		lateinit var wac: WebApplicationContext

		// ...
	}
----
--


.Class hierarchy with implicit parent context
--
The test classes in this example define a context hierarchy within a test class
hierarchy. `AbstractWebTests` declares the configuration for a root
`WebApplicationContext` in a Spring-powered web application. Note, however, that
`AbstractWebTests` does not declare `@ContextHierarchy`. Consequently, subclasses of
`AbstractWebTests` can optionally participate in a context hierarchy or follow the
standard semantics for `@ContextConfiguration`. `SoapWebServiceTests` and
`RestWebServiceTests` both extend `AbstractWebTests` and define a context hierarchy by
using `@ContextHierarchy`. The result is that three application contexts are loaded (one
for each declaration of `@ContextConfiguration`), and the application context loaded
based on the configuration in `AbstractWebTests` is set as the parent context for each of
the contexts loaded for the concrete subclasses. The following listing shows this
configuration scenario:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@ExtendWith(SpringExtension.class)
	@WebAppConfiguration
	@ContextConfiguration("file:src/main/webapp/WEB-INF/applicationContext.xml")
	public abstract class AbstractWebTests {}

	@ContextHierarchy(@ContextConfiguration("/spring/soap-ws-config.xml"))
	public class SoapWebServiceTests extends AbstractWebTests {}

	@ContextHierarchy(@ContextConfiguration("/spring/rest-ws-config.xml"))
	public class RestWebServiceTests extends AbstractWebTests {}
----
[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@ExtendWith(SpringExtension::class)
	@WebAppConfiguration
	@ContextConfiguration("file:src/main/webapp/WEB-INF/applicationContext.xml")
	abstract class AbstractWebTests

	@ContextHierarchy(ContextConfiguration("/spring/soap-ws-config.xml"))
	class SoapWebServiceTests : AbstractWebTests()

	@ContextHierarchy(ContextConfiguration("/spring/rest-ws-config.xml"))
	class RestWebServiceTests : AbstractWebTests()

----
--

.Class hierarchy with merged context hierarchy configuration
--
The classes in this example show the use of named hierarchy levels in order to merge the
configuration for specific levels in a context hierarchy. `BaseTests` defines two levels
in the hierarchy, `parent` and `child`. `ExtendedTests` extends `BaseTests` and instructs
the Spring TestContext Framework to merge the context configuration for the `child`
hierarchy level, by ensuring that the names declared in the `name` attribute in
`@ContextConfiguration` are both `child`. The result is that three application contexts
are loaded: one for `/app-config.xml`, one for `/user-config.xml`, and one for
`{"/user-config.xml", "/order-config.xml"}`. As with the previous example, the
application context loaded from `/app-config.xml` is set as the parent context for the
contexts loaded from `/user-config.xml` and `{"/user-config.xml", "/order-config.xml"}`.
The following listing shows this configuration scenario:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@ExtendWith(SpringExtension.class)
	@ContextHierarchy({
		@ContextConfiguration(name = "parent", locations = "/app-config.xml"),
		@ContextConfiguration(name = "child", locations = "/user-config.xml")
	})
	class BaseTests {}

	@ContextHierarchy(
		@ContextConfiguration(name = "child", locations = "/order-config.xml")
	)
	class ExtendedTests extends BaseTests {}
----

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@ExtendWith(SpringExtension::class)
	@ContextHierarchy(
		ContextConfiguration(name = "parent", locations = ["/app-config.xml"]),
		ContextConfiguration(name = "child", locations = ["/user-config.xml"]))
	open class BaseTests {}

	@ContextHierarchy(
		ContextConfiguration(name = "child", locations = ["/order-config.xml"])
	)
	class ExtendedTests : BaseTests() {}
----
--

.Class hierarchy with overridden context hierarchy configuration
--
In contrast to the previous example, this example demonstrates how to override the
configuration for a given named level in a context hierarchy by setting the
`inheritLocations` flag in `@ContextConfiguration` to `false`. Consequently, the
application context for `ExtendedTests` is loaded only from `/test-user-config.xml` and
has its parent set to the context loaded from `/app-config.xml`. The following listing
shows this configuration scenario:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@ExtendWith(SpringExtension.class)
	@ContextHierarchy({
		@ContextConfiguration(name = "parent", locations = "/app-config.xml"),
		@ContextConfiguration(name = "child", locations = "/user-config.xml")
	})
	class BaseTests {}

	@ContextHierarchy(
		@ContextConfiguration(
			name = "child",
			locations = "/test-user-config.xml",
			inheritLocations = false
	))
	class ExtendedTests extends BaseTests {}
----
[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@ExtendWith(SpringExtension::class)
	@ContextHierarchy(
		ContextConfiguration(name = "parent", locations = ["/app-config.xml"]),
		ContextConfiguration(name = "child", locations = ["/user-config.xml"]))
	open class BaseTests {}

	@ContextHierarchy(
			ContextConfiguration(
					name = "child",
					locations = ["/test-user-config.xml"],
					inheritLocations = false
			))
	class ExtendedTests : BaseTests() {}
----

.Dirtying a context within a context hierarchy
NOTE: If you use `@DirtiesContext` in a test whose context is configured as part of a
context hierarchy, you can use the `hierarchyMode` flag to control how the context cache
is cleared. For further details, see the discussion of `@DirtiesContext` in
<<spring-testing-annotation-dirtiescontext, Spring Testing Annotations>> and the
{api-spring-framework}/test/annotation/DirtiesContext.html[`@DirtiesContext`] javadoc.
--

[[testcontext-fixture-di]]
==== Dependency Injection of Test Fixtures

When you use the `DependencyInjectionTestExecutionListener` (which is configured by
default), the dependencies of your test instances are injected from beans in the
application context that you configured with `@ContextConfiguration` or related
annotations. You may use setter injection, field injection, or both, depending on
which annotations you choose and whether you place them on setter methods or fields.
If you are using JUnit Jupiter you may also optionally use constructor injection
(see <<testcontext-junit-jupiter-di>>). For consistency with Spring's annotation-based
injection support, you may also use Spring's `@Autowired` annotation or the `@Inject`
annotation from JSR-330 for field and setter injection.

TIP: For testing frameworks other than JUnit Jupiter, the TestContext framework does not
participate in instantiation of the test class. Thus, the use of `@Autowired` or
`@Inject` for constructors has no effect for test classes.

NOTE: Although field injection is discouraged in production code, field injection is
actually quite natural in test code. The rationale for the difference is that you will
never instantiate your test class directly. Consequently, there is no need to be able to
invoke a `public` constructor or setter method on your test class.

Because `@Autowired` is used to perform <<core.adoc#beans-factory-autowire, autowiring by
type>>, if you have multiple bean definitions of the same type, you cannot rely on this
approach for those particular beans. In that case, you can use `@Autowired` in
conjunction with `@Qualifier`. You can also choose to use `@Inject` in conjunction with
`@Named`. Alternatively, if your test class has access to its `ApplicationContext`, you
can perform an explicit lookup by using (for example) a call to
`applicationContext.getBean("titleRepository", TitleRepository.class)`.

If you do not want dependency injection applied to your test instances, do not annotate
fields or setter methods with `@Autowired` or `@Inject`. Alternatively, you can disable
dependency injection altogether by explicitly configuring your class with
`@TestExecutionListeners` and omitting `DependencyInjectionTestExecutionListener.class`
from the list of listeners.

Consider the scenario of testing a `HibernateTitleRepository` class, as outlined in the
<<integration-testing-goals, Goals>> section. The next two code listings demonstrate the
use of `@Autowired` on fields and setter methods. The application context configuration
is presented after all sample code listings.

[NOTE]
====
The dependency injection behavior in the following code listings is not specific to JUnit
Jupiter. The same DI techniques can be used in conjunction with any supported testing
framework.

The following examples make calls to static assertion methods, such as `assertNotNull()`,
but without prepending the call with `Assertions`. In such cases, assume that the method
was properly imported through an `import static` declaration that is not shown in the
example.
====

The first code listing shows a JUnit Jupiter based implementation of the test class that
uses `@Autowired` for field injection:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@ExtendWith(SpringExtension.class)
	// specifies the Spring configuration to load for this test fixture
	@ContextConfiguration("repository-config.xml")
	class HibernateTitleRepositoryTests {

		// this instance will be dependency injected by type
		@Autowired
		HibernateTitleRepository titleRepository;

		@Test
		void findById() {
			Title title = titleRepository.findById(new Long(10));
			assertNotNull(title);
		}
	}
----

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@ExtendWith(SpringExtension::class)
	// specifies the Spring configuration to load for this test fixture
	@ContextConfiguration("repository-config.xml")
	class HibernateTitleRepositoryTests {

		// this instance will be dependency injected by type
		@Autowired
		lateinit var titleRepository: HibernateTitleRepository

		@Test
		fun findById() {
			val title = titleRepository.findById(10)
			assertNotNull(title)
		}
	}
----

Alternatively, you can configure the class to use `@Autowired` for setter injection, as
follows:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@ExtendWith(SpringExtension.class)
	// specifies the Spring configuration to load for this test fixture
	@ContextConfiguration("repository-config.xml")
	class HibernateTitleRepositoryTests {

		// this instance will be dependency injected by type
		HibernateTitleRepository titleRepository;

		@Autowired
		void setTitleRepository(HibernateTitleRepository titleRepository) {
			this.titleRepository = titleRepository;
		}

		@Test
		void findById() {
			Title title = titleRepository.findById(new Long(10));
			assertNotNull(title);
		}
	}
----

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@ExtendWith(SpringExtension::class)
	// specifies the Spring configuration to load for this test fixture
	@ContextConfiguration("repository-config.xml")
	class HibernateTitleRepositoryTests {

		// this instance will be dependency injected by type
		lateinit var titleRepository: HibernateTitleRepository

		@Autowired
		fun setTitleRepository(titleRepository: HibernateTitleRepository) {
			this.titleRepository = titleRepository
		}

		@Test
		fun findById() {
			val title = titleRepository.findById(10)
			assertNotNull(title)
		}
	}
----

The preceding code listings use the same XML context file referenced by the
`@ContextConfiguration` annotation (that is, `repository-config.xml`). The following
shows this configuration:

[source,xml,indent=0]
[subs="verbatim,quotes"]
----
	<?xml version="1.0" encoding="UTF-8"?>
	<beans xmlns="http://www.springframework.org/schema/beans"
		xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
		xsi:schemaLocation="http://www.springframework.org/schema/beans
			https://www.springframework.org/schema/beans/spring-beans.xsd">

		<!-- this bean will be injected into the HibernateTitleRepositoryTests class -->
		<bean id="titleRepository" class="com.foo.repository.hibernate.HibernateTitleRepository">
			<property name="sessionFactory" ref="sessionFactory"/>
		</bean>

		<bean id="sessionFactory" class="org.springframework.orm.hibernate5.LocalSessionFactoryBean">
			<!-- configuration elided for brevity -->
		</bean>

	</beans>
----

[NOTE]
=====
If you are extending from a Spring-provided test base class that happens to use
`@Autowired` on one of its setter methods, you might have multiple beans of the affected
type defined in your application context (for example, multiple `DataSource` beans). In
such a case, you can override the setter method and use the `@Qualifier` annotation to
indicate a specific target bean, as follows (but make sure to delegate to the overridden
method in the superclass as well):

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	// ...

		@Autowired
		@Override
		public void setDataSource(@Qualifier("myDataSource") DataSource dataSource) {
			super.setDataSource(dataSource);
		}

	// ...
----

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	// ...

		@Autowired
		override fun setDataSource(@Qualifier("myDataSource") dataSource: DataSource) {
			super.setDataSource(dataSource)
		}

	// ...
----

The specified qualifier value indicates the specific `DataSource` bean to inject,
narrowing the set of type matches to a specific bean. Its value is matched against
`<qualifier>` declarations within the corresponding `<bean>` definitions. The bean name
is used as a fallback qualifier value, so you can effectively also point to a specific
bean by name there (as shown earlier, assuming that `myDataSource` is the bean `id`).
=====


[[testcontext-web-scoped-beans]]
==== Testing Request- and Session-scoped Beans

Spring has supported <<core#beans-factory-scopes-other, Request- and session-scoped
beans>> since the early years, and you can test your request-scoped and session-scoped
beans by following these steps:

* Ensure that a `WebApplicationContext` is loaded for your test by annotating your test
  class with `@WebAppConfiguration`.
* Inject the mock request or session into your test instance and prepare your test
  fixture as appropriate.
* Invoke your web component that you retrieved from the configured
  `WebApplicationContext` (with dependency injection).
* Perform assertions against the mocks.

The next code snippet shows the XML configuration for a login use case. Note that the
`userService` bean has a dependency on a request-scoped `loginAction` bean. Also, the
`LoginAction` is instantiated by using <<core.adoc#expressions, SpEL expressions>> that
retrieve the username and password from the current HTTP request. In our test, we want to
configure these request parameters through the mock managed by the TestContext framework.
The following listing shows the configuration for this use case:

.Request-scoped bean configuration
[source,xml,indent=0]
----
	<beans>

		<bean id="userService" class="com.example.SimpleUserService"
				c:loginAction-ref="loginAction"/>

		<bean id="loginAction" class="com.example.LoginAction"
				c:username="#{request.getParameter('user')}"
				c:password="#{request.getParameter('pswd')}"
				scope="request">
			<aop:scoped-proxy/>
		</bean>

	</beans>
----

In `RequestScopedBeanTests`, we inject both the `UserService` (that is, the subject under
test) and the `MockHttpServletRequest` into our test instance. Within our
`requestScope()` test method, we set up our test fixture by setting request parameters in
the provided `MockHttpServletRequest`. When the `loginUser()` method is invoked on our
`userService`, we are assured that the user service has access to the request-scoped
`loginAction` for the current `MockHttpServletRequest` (that is, the one in which we just
set parameters). We can then perform assertions against the results based on the known
inputs for the username and password. The following listing shows how to do so:

.Request-scoped bean test
[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@SpringJUnitWebConfig
	class RequestScopedBeanTests {

		@Autowired UserService userService;
		@Autowired MockHttpServletRequest request;

		@Test
		void requestScope() {
			request.setParameter("user", "enigma");
			request.setParameter("pswd", "$pr!ng");

			LoginResults results = userService.loginUser();
			// assert results
		}
	}
----
[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@SpringJUnitWebConfig
	class RequestScopedBeanTests {

		@Autowired lateinit var userService: UserService
		@Autowired lateinit var request: MockHttpServletRequest

		@Test
		fun requestScope() {
			request.setParameter("user", "enigma")
			request.setParameter("pswd", "\$pr!ng")

			val results = userService.loginUser()
			// assert results
		}
	}
----

The following code snippet is similar to the one we saw earlier for a request-scoped
bean. However, this time, the `userService` bean has a dependency on a session-scoped
`userPreferences` bean. Note that the `UserPreferences` bean is instantiated by using a
SpEL expression that retrieves the theme from the current HTTP session. In our test, we
need to configure a theme in the mock session managed by the TestContext framework. The
following example shows how to do so:

.Session-scoped bean configuration
[source,xml,indent=0]
[subs="verbatim,quotes"]
----
	<beans>

		<bean id="userService" class="com.example.SimpleUserService"
				c:userPreferences-ref="userPreferences" />

		<bean id="userPreferences" class="com.example.UserPreferences"
				c:theme="#{session.getAttribute('theme')}"
				scope="session">
			<aop:scoped-proxy/>
		</bean>

	</beans>
----

In `SessionScopedBeanTests`, we inject the `UserService` and the `MockHttpSession` into
our test instance. Within our `sessionScope()` test method, we set up our test fixture by
setting the expected `theme` attribute in the provided `MockHttpSession`. When the
`processUserPreferences()` method is invoked on our `userService`, we are assured that
the user service has access to the session-scoped `userPreferences` for the current
`MockHttpSession`, and we can perform assertions against the results based on the
configured theme. The following example shows how to do so:

.Session-scoped bean test
[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@SpringJUnitWebConfig
	class SessionScopedBeanTests {

		@Autowired UserService userService;
		@Autowired MockHttpSession session;

		@Test
		void sessionScope() throws Exception {
			session.setAttribute("theme", "blue");

			Results results = userService.processUserPreferences();
			// assert results
		}
	}
----

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@SpringJUnitWebConfig
	class SessionScopedBeanTests {

		@Autowired lateinit var userService: UserService
		@Autowired lateinit var session: MockHttpSession

		@Test
		fun sessionScope() {
			session.setAttribute("theme", "blue")

			val results = userService.processUserPreferences()
			// assert results
		}
	}
----

[[testcontext-tx]]
==== Transaction Management

In the TestContext framework, transactions are managed by the
`TransactionalTestExecutionListener`, which is configured by default, even if you do not
explicitly declare `@TestExecutionListeners` on your test class. To enable support for
transactions, however, you must configure a `PlatformTransactionManager` bean in the
`ApplicationContext` that is loaded with `@ContextConfiguration` semantics (further
details are provided later). In addition, you must declare Spring's `@Transactional`
annotation either at the class or the method level for your tests.

[[testcontext-tx-test-managed-transactions]]
===== Test-managed Transactions

Test-managed transactions are transactions that are managed declaratively by using the
`TransactionalTestExecutionListener` or programmatically by using `TestTransaction`
(described later). You should not confuse such transactions with Spring-managed
transactions (those managed directly by Spring within the `ApplicationContext` loaded for
tests) or application-managed transactions (those managed programmatically within
application code that is invoked by tests). Spring-managed and application-managed
transactions typically participate in test-managed transactions. However, you should use
caution if Spring-managed or application-managed transactions are configured with any
propagation type other than `REQUIRED` or `SUPPORTS` (see the discussion on
<<data-access.adoc#tx-propagation, transaction propagation>> for details).

.Preemptive timeouts and test-managed transactions
[WARNING]
====
Caution must be taken when using any form of preemptive timeouts from a testing framework
in conjunction with Spring's test-managed transactions.

Specifically, Spring’s testing support binds transaction state to the current thread (via
a `java.lang.ThreadLocal` variable) _before_ the current test method is invoked. If a
testing framework invokes the current test method in a new thread in order to support a
preemptive timeout, any actions performed within the current test method will _not_ be
invoked within the test-managed transaction. Consequently, the result of any such actions
will not be rolled back with the test-managed transaction. On the contrary, such actions
will be committed to the persistent store -- for example, a relational database -- even
though the test-managed transaction is properly rolled back by Spring.

Situations in which this can occur include but are not limited to the following.

* JUnit 4's `@Test(timeout = ...)` support and `TimeOut` rule
* JUnit Jupiter's `assertTimeoutPreemptively(...)` methods in the
  `org.junit.jupiter.api.Assertions` class
* TestNG's `@Test(timeOut = ...)` support
====

[[testcontext-tx-enabling-transactions]]
===== Enabling and Disabling Transactions

Annotating a test method with `@Transactional` causes the test to be run within a
transaction that is, by default, automatically rolled back after completion of the test.
If a test class is annotated with `@Transactional`, each test method within that class
hierarchy runs within a transaction. Test methods that are not annotated with
`@Transactional` (at the class or method level) are not run within a transaction. Note
that `@Transactional` is not supported on test lifecycle methods — for example, methods
annotated with JUnit Jupiter's `@BeforeAll`, `@BeforeEach`, etc. Furthermore, tests that
are annotated with `@Transactional` but have the `propagation` attribute set to
`NOT_SUPPORTED` are not run within a transaction.

[[testcontext-tx-attribute-support]]
.`@Transactional` attribute support
|===
|Attribute |Supported for test-managed transactions

|`value` and `transactionManager` |yes

|`propagation` |only `Propagation.NOT_SUPPORTED` is supported

|`isolation` |no

|`timeout` |no

|`readOnly` |no

|`rollbackFor` and `rollbackForClassName` |no: use `TestTransaction.flagForRollback()` instead

|`noRollbackFor` and `noRollbackForClassName` |no: use `TestTransaction.flagForCommit()` instead
|===

[TIP]
====
Method-level lifecycle methods — for example, methods annotated with JUnit Jupiter's
`@BeforeEach` or `@AfterEach` — are run within a test-managed transaction. On the other
hand, suite-level and class-level lifecycle methods — for example, methods annotated with
JUnit Jupiter's `@BeforeAll` or `@AfterAll` and methods annotated with TestNG's
`@BeforeSuite`, `@AfterSuite`, `@BeforeClass`, or `@AfterClass` — are _not_ run within a
test-managed transaction.

If you need to execute code in a suite-level or class-level lifecycle method within a
transaction, you may wish to inject a corresponding `PlatformTransactionManager` into
your test class and then use that with a `TransactionTemplate` for programmatic
transaction management.
====

Note that <<testcontext-support-classes-junit4,
`AbstractTransactionalJUnit4SpringContextTests`>> and
<<testcontext-support-classes-testng, `AbstractTransactionalTestNGSpringContextTests`>>
are preconfigured for transactional support at the class level.

The following example demonstrates a common scenario for writing an integration test for
a Hibernate-based `UserRepository`:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@SpringJUnitConfig(TestConfig.class)
	@Transactional
	class HibernateUserRepositoryTests {

		@Autowired
		HibernateUserRepository repository;

		@Autowired
		SessionFactory sessionFactory;

		JdbcTemplate jdbcTemplate;

		@Autowired
		void setDataSource(DataSource dataSource) {
			this.jdbcTemplate = new JdbcTemplate(dataSource);
		}

		@Test
		void createUser() {
			// track initial state in test database:
			final int count = countRowsInTable("user");

			User user = new User(...);
			repository.save(user);

			// Manual flush is required to avoid false positive in test
			sessionFactory.getCurrentSession().flush();
			assertNumUsers(count + 1);
		}

		private int countRowsInTable(String tableName) {
			return JdbcTestUtils.countRowsInTable(this.jdbcTemplate, tableName);
		}

		private void assertNumUsers(int expected) {
			assertEquals("Number of rows in the [user] table.", expected, countRowsInTable("user"));
		}
	}
----

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@SpringJUnitConfig(TestConfig::class)
	@Transactional
	class HibernateUserRepositoryTests {

		@Autowired
		lateinit var repository: HibernateUserRepository

		@Autowired
		lateinit var sessionFactory: SessionFactory

		lateinit var jdbcTemplate: JdbcTemplate

		@Autowired
		fun setDataSource(dataSource: DataSource) {
			this.jdbcTemplate = JdbcTemplate(dataSource)
		}

		@Test
		fun createUser() {
			// track initial state in test database:
			val count = countRowsInTable("user")

			val user = User()
			repository.save(user)

			// Manual flush is required to avoid false positive in test
			sessionFactory.getCurrentSession().flush()
			assertNumUsers(count + 1)
		}

		private fun countRowsInTable(tableName: String): Int {
			return JdbcTestUtils.countRowsInTable(jdbcTemplate, tableName)
		}

		private fun assertNumUsers(expected: Int) {
			assertEquals("Number of rows in the [user] table.", expected, countRowsInTable("user"))
		}
	}
----

As explained in <<testcontext-tx-rollback-and-commit-behavior>>, there is no need to
clean up the database after the `createUser()` method runs, since any changes made to the
database are automatically rolled back by the `TransactionalTestExecutionListener`.

[[testcontext-tx-rollback-and-commit-behavior]]
===== Transaction Rollback and Commit Behavior

By default, test transactions will be automatically rolled back after completion of the
test; however, transactional commit and rollback behavior can be configured declaratively
via the `@Commit` and `@Rollback` annotations. See the corresponding entries in the
<<integration-testing-annotations, annotation support>> section for further details.

[[testcontext-tx-programmatic-tx-mgt]]
===== Programmatic Transaction Management

You can interact with test-managed transactions programmatically by using the static
methods in `TestTransaction`. For example, you can use `TestTransaction` within test
methods, before methods, and after methods to start or end the current test-managed
transaction or to configure the current test-managed transaction for rollback or commit.
Support for `TestTransaction` is automatically available whenever the
`TransactionalTestExecutionListener` is enabled.

The following example demonstrates some of the features of `TestTransaction`. See the
javadoc for {api-spring-framework}/test/context/transaction/TestTransaction.html[`TestTransaction`]
for further details.

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@ContextConfiguration(classes = TestConfig.class)
	public class ProgrammaticTransactionManagementTests extends
			AbstractTransactionalJUnit4SpringContextTests {

		@Test
		public void transactionalTest() {
			// assert initial state in test database:
			assertNumUsers(2);

			deleteFromTables("user");

			// changes to the database will be committed!
			TestTransaction.flagForCommit();
			TestTransaction.end();
			assertFalse(TestTransaction.isActive());
			assertNumUsers(0);

			TestTransaction.start();
			// perform other actions against the database that will
			// be automatically rolled back after the test completes...
		}

		protected void assertNumUsers(int expected) {
			assertEquals("Number of rows in the [user] table.", expected, countRowsInTable("user"));
		}
	}
----
[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@ContextConfiguration(classes = [TestConfig::class])
	class ProgrammaticTransactionManagementTests : AbstractTransactionalJUnit4SpringContextTests() {

		@Test
		fun transactionalTest() {
			// assert initial state in test database:
			assertNumUsers(2)

			deleteFromTables("user")

			// changes to the database will be committed!
			TestTransaction.flagForCommit()
			TestTransaction.end()
			assertFalse(TestTransaction.isActive())
			assertNumUsers(0)

			TestTransaction.start()
			// perform other actions against the database that will
			// be automatically rolled back after the test completes...
		}

		protected fun assertNumUsers(expected: Int) {
			assertEquals("Number of rows in the [user] table.", expected, countRowsInTable("user"))
		}
	}
----

[[testcontext-tx-before-and-after-tx]]
===== Running Code Outside of a Transaction

Occasionally, you may need to execute certain code before or after a transactional test
method but outside the transactional context -- for example, to verify the initial
database state prior to running your test or to verify expected transactional commit
behavior after your test runs (if the test was configured to commit the transaction).
`TransactionalTestExecutionListener` supports the `@BeforeTransaction` and
`@AfterTransaction` annotations for exactly such scenarios. You can annotate any `void`
method in a test class or any `void` default method in a test interface with one of these
annotations, and the `TransactionalTestExecutionListener` ensures that your before
transaction method or after transaction method runs at the appropriate time.

TIP: Any before methods (such as methods annotated with JUnit Jupiter's `@BeforeEach`)
and any after methods (such as methods annotated with JUnit Jupiter's `@AfterEach`) are
run within a transaction. In addition, methods annotated with `@BeforeTransaction` or
`@AfterTransaction` are not run for test methods that are not configured to run within a
transaction.

[[testcontext-tx-mgr-config]]
===== Configuring a Transaction Manager

`TransactionalTestExecutionListener` expects a `PlatformTransactionManager` bean to be
defined in the Spring `ApplicationContext` for the test. If there are multiple instances
of `PlatformTransactionManager` within the test's `ApplicationContext`, you can declare a
qualifier by using `@Transactional("myTxMgr")` or `@Transactional(transactionManager =
"myTxMgr")`, or `TransactionManagementConfigurer` can be implemented by an
`@Configuration` class. Consult the
{api-spring-framework}/test/context/transaction/TestContextTransactionUtils.html#retrieveTransactionManager-org.springframework.test.context.TestContext-java.lang.String-[javadoc
for `TestContextTransactionUtils.retrieveTransactionManager()`] for details on the
algorithm used to look up a transaction manager in the test's `ApplicationContext`.

[[testcontext-tx-annotation-demo]]
===== Demonstration of All Transaction-related Annotations

The following JUnit Jupiter based example displays a fictitious integration testing
scenario that highlights all transaction-related annotations. The example is not intended
to demonstrate best practices but rather to demonstrate how these annotations can be
used. See the <<integration-testing-annotations, annotation support>> section for further
information and configuration examples. <<testcontext-executing-sql-declaratively-tx,
Transaction management for `@Sql`>> contains an additional example that uses `@Sql` for
declarative SQL script execution with default transaction rollback semantics. The
following example shows the relevant annotations:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@SpringJUnitConfig
	@Transactional(transactionManager = "txMgr")
	@Commit
	class FictitiousTransactionalTest {

		@BeforeTransaction
		void verifyInitialDatabaseState() {
			// logic to verify the initial state before a transaction is started
		}

		@BeforeEach
		void setUpTestDataWithinTransaction() {
			// set up test data within the transaction
		}

		@Test
		// overrides the class-level @Commit setting
		@Rollback
		void modifyDatabaseWithinTransaction() {
			// logic which uses the test data and modifies database state
		}

		@AfterEach
		void tearDownWithinTransaction() {
			// execute "tear down" logic within the transaction
		}

		@AfterTransaction
		void verifyFinalDatabaseState() {
			// logic to verify the final state after transaction has rolled back
		}

	}
----

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@SpringJUnitConfig
	@Transactional(transactionManager = "txMgr")
	@Commit
	class FictitiousTransactionalTest {

		@BeforeTransaction
		fun verifyInitialDatabaseState() {
			// logic to verify the initial state before a transaction is started
		}

		@BeforeEach
		fun setUpTestDataWithinTransaction() {
			// set up test data within the transaction
		}

		@Test
		// overrides the class-level @Commit setting
		@Rollback
		fun modifyDatabaseWithinTransaction() {
			// logic which uses the test data and modifies database state
		}

		@AfterEach
		fun tearDownWithinTransaction() {
			// execute "tear down" logic within the transaction
		}

		@AfterTransaction
		fun verifyFinalDatabaseState() {
			// logic to verify the final state after transaction has rolled back
		}

	}
----

[[testcontext-tx-false-positives]]
.Avoid false positives when testing ORM code

[NOTE]
=====
When you test application code that manipulates the state of a Hibernate session or JPA
persistence context, make sure to flush the underlying unit of work within test methods
that run that code. Failing to flush the underlying unit of work can produce false
positives: Your test passes, but the same code throws an exception in a live, production
environment. Note that this applies to any ORM framework that maintains an in-memory unit
of work. In the following Hibernate-based example test case, one method demonstrates a
false positive, and the other method correctly exposes the results of flushing the
session:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	// ...

	@Autowired
	SessionFactory sessionFactory;

	@Transactional
	@Test // no expected exception!
	public void falsePositive() {
		updateEntityInHibernateSession();
		// False positive: an exception will be thrown once the Hibernate
		// Session is finally flushed (i.e., in production code)
	}

	@Transactional
	@Test(expected = ...)
	public void updateWithSessionFlush() {
		updateEntityInHibernateSession();
		// Manual flush is required to avoid false positive in test
		sessionFactory.getCurrentSession().flush();
	}

	// ...
----

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	// ...

	@Autowired
	lateinit var sessionFactory: SessionFactory

	@Transactional
	@Test // no expected exception!
	fun falsePositive() {
		updateEntityInHibernateSession()
		// False positive: an exception will be thrown once the Hibernate
		// Session is finally flushed (i.e., in production code)
	}

	@Transactional
	@Test(expected = ...)
	fun updateWithSessionFlush() {
		updateEntityInHibernateSession()
		// Manual flush is required to avoid false positive in test
		sessionFactory.getCurrentSession().flush()
	}

	// ...
----

The following example shows matching methods for JPA:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	// ...

	@PersistenceContext
	EntityManager entityManager;

	@Transactional
	@Test // no expected exception!
	public void falsePositive() {
		updateEntityInJpaPersistenceContext();
		// False positive: an exception will be thrown once the JPA
		// EntityManager is finally flushed (i.e., in production code)
	}

	@Transactional
	@Test(expected = ...)
	public void updateWithEntityManagerFlush() {
		updateEntityInJpaPersistenceContext();
		// Manual flush is required to avoid false positive in test
		entityManager.flush();
	}

	// ...
----
[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	// ...

	@PersistenceContext
	lateinit var entityManager:EntityManager

	@Transactional
	@Test // no expected exception!
	fun falsePositive() {
		updateEntityInJpaPersistenceContext()
		// False positive: an exception will be thrown once the JPA
		// EntityManager is finally flushed (i.e., in production code)
	}

	@Transactional
	@Test(expected = ...)
	void updateWithEntityManagerFlush() {
		updateEntityInJpaPersistenceContext()
		// Manual flush is required to avoid false positive in test
		entityManager.flush()
	}

	// ...
----
=====


[[testcontext-executing-sql]]
==== Executing SQL Scripts

When writing integration tests against a relational database, it is often beneficial to
execute SQL scripts to modify the database schema or insert test data into tables. The
`spring-jdbc` module provides support for _initializing_ an embedded or existing database
by executing SQL scripts when the Spring `ApplicationContext` is loaded. See
<<data-access.adoc#jdbc-embedded-database-support, Embedded database support>> and
<<data-access.adoc#jdbc-embedded-database-dao-testing, Testing data access logic with an
embedded database>> for details.

Although it is very useful to initialize a database for testing _once_ when the
`ApplicationContext` is loaded, sometimes it is essential to be able to modify the
database _during_ integration tests. The following sections explain how to execute SQL
scripts programmatically and declaratively during integration tests.

[[testcontext-executing-sql-programmatically]]
===== Executing SQL scripts programmatically

Spring provides the following options for executing SQL scripts programmatically within
integration test methods.

* `org.springframework.jdbc.datasource.init.ScriptUtils`
* `org.springframework.jdbc.datasource.init.ResourceDatabasePopulator`
* `org.springframework.test.context.junit4.AbstractTransactionalJUnit4SpringContextTests`
* `org.springframework.test.context.testng.AbstractTransactionalTestNGSpringContextTests`

`ScriptUtils` provides a collection of static utility methods for working with SQL
scripts and is mainly intended for internal use within the framework. However, if you
require full control over how SQL scripts are parsed and executed, `ScriptUtils` may suit
your needs better than some of the other alternatives described later. See the
{api-spring-framework}/jdbc/datasource/init/ScriptUtils.html[javadoc] for individual
methods in `ScriptUtils` for further details.

`ResourceDatabasePopulator` provides an object-based API for programmatically populating,
initializing, or cleaning up a database by using SQL scripts defined in external
resources. `ResourceDatabasePopulator` provides options for configuring the character
encoding, statement separator, comment delimiters, and error handling flags used when
parsing and running the scripts. Each of the configuration options has a reasonable
default value. See the
{api-spring-framework}/jdbc/datasource/init/ResourceDatabasePopulator.html[javadoc] for
details on default values. To run the scripts configured in a
`ResourceDatabasePopulator`, you can invoke either the `populate(Connection)` method to
execute the populator against a `java.sql.Connection` or the `execute(DataSource)` method
to execute the populator against a `javax.sql.DataSource`. The following example
specifies SQL scripts for a test schema and test data, sets the statement separator to
`@@`, and executes the scripts against a `DataSource`:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@Test
	void databaseTest() {
		ResourceDatabasePopulator populator = new ResourceDatabasePopulator();
		populator.addScripts(
				new ClassPathResource("test-schema.sql"),
				new ClassPathResource("test-data.sql"));
		populator.setSeparator("@@");
		populator.execute(this.dataSource);
		// execute code that uses the test schema and data
	}
----
[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@Test
	fun databaseTest() {
		val populator = ResourceDatabasePopulator()
		populator.addScripts(
				ClassPathResource("test-schema.sql"),
				ClassPathResource("test-data.sql"))
		populator.setSeparator("@@")
		populator.execute(dataSource)
		// execute code that uses the test schema and data
	}
----

Note that `ResourceDatabasePopulator` internally delegates to `ScriptUtils` for parsing
and running SQL scripts. Similarly, the `executeSqlScript(..)` methods in
<<testcontext-support-classes-junit4, `AbstractTransactionalJUnit4SpringContextTests`>>
and <<testcontext-support-classes-testng, `AbstractTransactionalTestNGSpringContextTests`>>
internally use a `ResourceDatabasePopulator` to run SQL scripts. See the javadoc for the
various `executeSqlScript(..)` methods for further details.

[[testcontext-executing-sql-declaratively]]
===== Executing SQL scripts declaratively with @Sql

In addition to the aforementioned mechanisms for running SQL scripts programmatically,
you can declaratively configure SQL scripts in the Spring TestContext Framework.
Specifically, you can declare the `@Sql` annotation on a test class or test method to
configure individual SQL statements or the resource paths to SQL scripts that should be
run against a given database before or after an integration test method. Support for
`@Sql` is provided by the `SqlScriptsTestExecutionListener`, which is enabled by default.

NOTE: Method-level `@Sql` declarations override class-level declarations by default. As
of Spring Framework 5.2, however, this behavior may be configured per test class or per
test method via `@SqlMergeMode`. See
<<testcontext-executing-sql-declaratively-script-merging>> for further details.

[[testcontext-executing-sql-declaratively-script-resources]]
====== Path Resource Semantics

Each path is interpreted as a Spring `Resource`. A plain path (for example,
`"schema.sql"`) is treated as a classpath resource that is relative to the package in
which the test class is defined. A path starting with a slash is treated as an absolute
classpath resource (for example, `"/org/example/schema.sql"`). A path that references a
URL (for example, a path prefixed with `classpath:`, `file:`, `http:`) is loaded by using
the specified resource protocol.

The following example shows how to use `@Sql` at the class level and at the method level
within a JUnit Jupiter based integration test class:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@SpringJUnitConfig
	@Sql("/test-schema.sql")
	class DatabaseTests {

		@Test
		void emptySchemaTest() {
			// execute code that uses the test schema without any test data
		}

		@Test
		@Sql({"/test-schema.sql", "/test-user-data.sql"})
		void userTest() {
			// execute code that uses the test schema and test data
		}
	}
----

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@SpringJUnitConfig
	@Sql("/test-schema.sql")
	class DatabaseTests {

		@Test
		fun emptySchemaTest() {
			// execute code that uses the test schema without any test data
		}

		@Test
		@Sql("/test-schema.sql", "/test-user-data.sql")
		fun userTest() {
			// execute code that uses the test schema and test data
		}
	}
----

[[testcontext-executing-sql-declaratively-script-detection]]
====== Default Script Detection

If no SQL scripts or statements are specified, an attempt is made to detect a `default`
script, depending on where `@Sql` is declared. If a default cannot be detected, an
`IllegalStateException` is thrown.

* Class-level declaration: If the annotated test class is `com.example.MyTest`, the
  corresponding default script is `classpath:com/example/MyTest.sql`.
* Method-level declaration: If the annotated test method is named `testMethod()` and is
  defined in the class `com.example.MyTest`, the corresponding default script is
  `classpath:com/example/MyTest.testMethod.sql`.

[[testcontext-executing-sql-declaratively-multiple-annotations]]
====== Declaring Multiple `@Sql` Sets

If you need to configure multiple sets of SQL scripts for a given test class or test
method but with different syntax configuration, different error handling rules, or
different execution phases per set, you can declare multiple instances of `@Sql`. With
Java 8, you can use `@Sql` as a repeatable annotation. Otherwise, you can use the
`@SqlGroup` annotation as an explicit container for declaring multiple instances of
`@Sql`.

The following example shows how to use `@Sql` as a repeatable annotation with Java 8:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@Test
	@Sql(scripts = "/test-schema.sql", config = @SqlConfig(commentPrefix = "`"))
	@Sql("/test-user-data.sql")
	void userTest() {
		// execute code that uses the test schema and test data
	}
----
[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	// Repeatable annotations with non-SOURCE retention are not yet supported by Kotlin
----

In the scenario presented in the preceding example, the `test-schema.sql` script uses a
different syntax for single-line comments.

The following example is identical to the preceding example, except that the `@Sql`
declarations are grouped together within `@SqlGroup`. With Java 8 and above, the use of
`@SqlGroup` is optional, but you may need to use `@SqlGroup` for compatibility with
other JVM languages such as Kotlin.

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@Test
	@SqlGroup({
		@Sql(scripts = "/test-schema.sql", config = @SqlConfig(commentPrefix = "`")),
		@Sql("/test-user-data.sql")
	)}
	void userTest() {
		// execute code that uses the test schema and test data
	}
----
[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@Test
	@SqlGroup(
		Sql("/test-schema.sql", config = SqlConfig(commentPrefix = "`")),
		Sql("/test-user-data.sql"))
	fun userTest() {
		// execute code that uses the test schema and test data
	}
----

[[testcontext-executing-sql-declaratively-script-execution-phases]]
====== Script Execution Phases

By default, SQL scripts are executed before the corresponding test method. However, if
you need to run a particular set of scripts after the test method (for example, to clean
up database state), you can use the `executionPhase` attribute in `@Sql`, as the
following example shows:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@Test
	@Sql(
		scripts = "create-test-data.sql",
		config = @SqlConfig(transactionMode = ISOLATED)
	)
	@Sql(
		scripts = "delete-test-data.sql",
		config = @SqlConfig(transactionMode = ISOLATED),
		executionPhase = AFTER_TEST_METHOD
	)
	void userTest() {
		// execute code that needs the test data to be committed
		// to the database outside of the test's transaction
	}
----
[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@Test
	@SqlGroup(
		Sql("create-test-data.sql",
			config = SqlConfig(transactionMode = ISOLATED)),
		Sql("delete-test-data.sql",
			config = SqlConfig(transactionMode = ISOLATED),
			executionPhase = AFTER_TEST_METHOD))
	fun userTest() {
		// execute code that needs the test data to be committed
		// to the database outside of the test's transaction
	}
----

Note that `ISOLATED` and `AFTER_TEST_METHOD` are statically imported from
`Sql.TransactionMode` and `Sql.ExecutionPhase`, respectively.

[[testcontext-executing-sql-declaratively-script-configuration]]
====== Script Configuration with `@SqlConfig`

You can configure script parsing and error handling by using the `@SqlConfig` annotation.
When declared as a class-level annotation on an integration test class, `@SqlConfig`
serves as global configuration for all SQL scripts within the test class hierarchy. When
declared directly by using the `config` attribute of the `@Sql` annotation, `@SqlConfig`
serves as local configuration for the SQL scripts declared within the enclosing `@Sql`
annotation. Every attribute in `@SqlConfig` has an implicit default value, which is
documented in the javadoc of the corresponding attribute. Due to the rules defined for
annotation attributes in the Java Language Specification, it is, unfortunately, not
possible to assign a value of `null` to an annotation attribute. Thus, in order to
support overrides of inherited global configuration, `@SqlConfig` attributes have an
explicit default value of either `""` (for Strings), `{}` (for arrays), or `DEFAULT` (for
enumerations). This approach lets local declarations of `@SqlConfig` selectively override
individual attributes from global declarations of `@SqlConfig` by providing a value other
than `""`, `{}`, or `DEFAULT`. Global `@SqlConfig` attributes are inherited whenever
local `@SqlConfig` attributes do not supply an explicit value other than `""`, `{}`, or
`DEFAULT`. Explicit local configuration, therefore, overrides global configuration.

The configuration options provided by `@Sql` and `@SqlConfig` are equivalent to those
supported by `ScriptUtils` and `ResourceDatabasePopulator` but are a superset of those
provided by the `<jdbc:initialize-database/>` XML namespace element. See the javadoc of
individual attributes in {api-spring-framework}/test/context/jdbc/Sql.html[`@Sql`] and
{api-spring-framework}/test/context/jdbc/SqlConfig.html[`@SqlConfig`] for details.

[[testcontext-executing-sql-declaratively-tx]]
*Transaction management for `@Sql`*

By default, the `SqlScriptsTestExecutionListener` infers the desired transaction
semantics for scripts configured by using `@Sql`. Specifically, SQL scripts are run
without a transaction, within an existing Spring-managed transaction (for example, a
transaction managed by the `TransactionalTestExecutionListener` for a test annotated with
`@Transactional`), or within an isolated transaction, depending on the configured value
of the `transactionMode` attribute in `@SqlConfig` and the presence of a
`PlatformTransactionManager` in the test's `ApplicationContext`. As a bare minimum,
however, a `javax.sql.DataSource` must be present in the test's `ApplicationContext`.

If the algorithms used by `SqlScriptsTestExecutionListener` to detect a `DataSource` and
`PlatformTransactionManager` and infer the transaction semantics do not suit your needs,
you can specify explicit names by setting the `dataSource` and `transactionManager`
attributes of `@SqlConfig`. Furthermore, you can control the transaction propagation
behavior by setting the `transactionMode` attribute of `@SqlConfig` (for example, whether
scripts should be run in an isolated transaction). Although a thorough discussion of all
supported options for transaction management with `@Sql` is beyond the scope of this
reference manual, the javadoc for
{api-spring-framework}/test/context/jdbc/SqlConfig.html[`@SqlConfig`] and
{api-spring-framework}/test/context/jdbc/SqlScriptsTestExecutionListener.html[`SqlScriptsTestExecutionListener`]
provide detailed information, and the following example shows a typical testing scenario
that uses JUnit Jupiter and transactional tests with `@Sql`:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@SpringJUnitConfig(TestDatabaseConfig.class)
	@Transactional
	class TransactionalSqlScriptsTests {

		final JdbcTemplate jdbcTemplate;

		@Autowired
		TransactionalSqlScriptsTests(DataSource dataSource) {
			this.jdbcTemplate = new JdbcTemplate(dataSource);
		}

		@Test
		@Sql("/test-data.sql")
		void usersTest() {
			// verify state in test database:
			assertNumUsers(2);
			// execute code that uses the test data...
		}

		int countRowsInTable(String tableName) {
			return JdbcTestUtils.countRowsInTable(this.jdbcTemplate, tableName);
		}

		void assertNumUsers(int expected) {
			assertEquals(expected, countRowsInTable("user"),
				"Number of rows in the [user] table.");
		}
	}
----
[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@SpringJUnitConfig(TestDatabaseConfig::class)
	@Transactional
	class TransactionalSqlScriptsTests @Autowired constructor(dataSource: DataSource) {

		val jdbcTemplate: JdbcTemplate = JdbcTemplate(dataSource)

		@Test
		@Sql("/test-data.sql")
		fun usersTest() {
			// verify state in test database:
			assertNumUsers(2)
			// execute code that uses the test data...
		}

		fun countRowsInTable(tableName: String): Int {
			return JdbcTestUtils.countRowsInTable(jdbcTemplate, tableName)
		}

		fun assertNumUsers(expected: Int) {
			assertEquals(expected, countRowsInTable("user"),
					"Number of rows in the [user] table.")
		}
	}
----

Note that there is no need to clean up the database after the `usersTest()` method is
run, since any changes made to the database (either within the test method or within the
`/test-data.sql` script) are automatically rolled back by the
`TransactionalTestExecutionListener` (see <<testcontext-tx,transaction management>> for
details).

[[testcontext-executing-sql-declaratively-script-merging]]
====== Merging and Overriding Configuration with `@SqlMergeMode`

As of Spring Framework 5.2, it is possible to merge method-level `@Sql` declarations with
class-level declarations. For example, this allows you to provide the configuration for a
database schema or some common test data once per test class and then provide additional,
use case specific test data per test method. To enable `@Sql` merging, annotate either
your test class or test method with `@SqlMergeMode(MERGE)`. To disable merging for a
specific test method (or specific test subclass), you can switch back to the default mode
via `@SqlMergeMode(OVERRIDE)`. Consult the <<spring-testing-annotation-sqlmergemode,
`@SqlMergeMode` annotation documentation section>> for examples and further details.


[[testcontext-parallel-test-execution]]
==== Parallel Test Execution

Spring Framework 5.0 introduced basic support for executing tests in parallel within a
single JVM when using the Spring TestContext Framework. In general, this means that most
test classes or test methods can be executed in parallel without any changes to test code
or configuration.

TIP: For details on how to set up parallel test execution, see the documentation for your
testing framework, build tool, or IDE.

Keep in mind that the introduction of concurrency into your test suite can result in
unexpected side effects, strange runtime behavior, and tests that fail intermittently or
seemingly randomly. The Spring Team therefore provides the following general guidelines
for when not to execute tests in parallel.

Do not execute tests in parallel if the tests:

* Use Spring Framework's `@DirtiesContext` support.
* Use Spring Boot's `@MockBean` or `@SpyBean` support.
* Use JUnit 4's `@FixMethodOrder` support or any testing framework feature
  that is designed to ensure that test methods run in a particular order. Note,
  however, that this does not apply if entire test classes are executed in parallel.
* Change the state of shared services or systems such as a database, message broker,
  filesystem, and others. This applies to both embedded and external systems.

[TIP]
====
If parallel test execution fails with an exception stating that the `ApplicationContext`
for the current test is no longer active, this typically means that the
`ApplicationContext` was removed from the `ContextCache` in a different thread.

This may be due to the use of `@DirtiesContext` or due to automatic eviction from the
`ContextCache`. If `@DirtiesContext` is the culprit, you either need to find a way to
avoid using `@DirtiesContext` or exclude such tests from parallel execution. If the
maximum size of the `ContextCache` has been exceeded, you can increase the maximum size
of the cache. See the discussion on <<testcontext-ctx-management-caching, context caching>>
for details.
====

WARNING: Parallel test execution in the Spring TestContext Framework is only possible if
the underlying `TestContext` implementation provides a copy constructor, as explained in
the javadoc for {api-spring-framework}/test/context/TestContext.html[`TestContext`]. The
`DefaultTestContext` used in Spring provides such a constructor. However, if you use a
third-party library that provides a custom `TestContext` implementation, you need to
verify that it is suitable for parallel test execution.


[[testcontext-support-classes]]
==== TestContext Framework Support Classes

This section describes the various classes that support the Spring TestContext Framework.

[[testcontext-junit4-runner]]
===== Spring JUnit 4 Runner

The Spring TestContext Framework offers full integration with JUnit 4 through a custom
runner (supported on JUnit 4.12 or higher). By annotating test classes with
`@RunWith(SpringJUnit4ClassRunner.class)` or the shorter `@RunWith(SpringRunner.class)`
variant, developers can implement standard JUnit 4-based unit and integration tests and
simultaneously reap the benefits of the TestContext framework, such as support for
loading application contexts, dependency injection of test instances, transactional test
method execution, and so on. If you want to use the Spring TestContext Framework with an
alternative runner (such as JUnit 4's `Parameterized` runner) or third-party runners
(such as the `MockitoJUnitRunner`), you can, optionally, use
<<testcontext-junit4-rules, Spring's support for JUnit rules>> instead.

The following code listing shows the minimal requirements for configuring a test class to
run with the custom Spring `Runner`:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@RunWith(SpringRunner.class)
	@TestExecutionListeners({})
	public class SimpleTest {

		@Test
		public void testMethod() {
			// execute test logic...
		}
	}
----

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@RunWith(SpringRunner::class)
	@TestExecutionListeners
	class SimpleTest {

		@Test
		fun testMethod() {
			// execute test logic...
		}
	}
----

In the preceding example, `@TestExecutionListeners` is configured with an empty list, to
disable the default listeners, which otherwise would require an `ApplicationContext` to
be configured through `@ContextConfiguration`.

[[testcontext-junit4-rules]]
===== Spring JUnit 4 Rules

The `org.springframework.test.context.junit4.rules` package provides the following JUnit
4 rules (supported on JUnit 4.12 or higher):

* `SpringClassRule`
* `SpringMethodRule`

`SpringClassRule` is a JUnit `TestRule` that supports class-level features of the Spring
TestContext Framework, whereas `SpringMethodRule` is a JUnit `MethodRule` that supports
instance-level and method-level features of the Spring TestContext Framework.

In contrast to the `SpringRunner`, Spring's rule-based JUnit support has the advantage of
being independent of any `org.junit.runner.Runner` implementation and can, therefore, be
combined with existing alternative runners (such as JUnit 4's `Parameterized`) or
third-party runners (such as the `MockitoJUnitRunner`).

To support the full functionality of the TestContext framework, you must combine a
`SpringClassRule` with a `SpringMethodRule`. The following example shows the proper way
to declare these rules in an integration test:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	// Optionally specify a non-Spring Runner via @RunWith(...)
	@ContextConfiguration
	public class IntegrationTest {

		@ClassRule
		public static final SpringClassRule springClassRule = new SpringClassRule();

		@Rule
		public final SpringMethodRule springMethodRule = new SpringMethodRule();

		@Test
		public void testMethod() {
			// execute test logic...
		}
	}
----

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	// Optionally specify a non-Spring Runner via @RunWith(...)
	@ContextConfiguration
	class IntegrationTest {

		@Rule
		val springMethodRule = SpringMethodRule()

		@Test
		fun testMethod() {
			// execute test logic...
		}

		companion object {
			@ClassRule
			val springClassRule = SpringClassRule()
		}
	}
----

[[testcontext-support-classes-junit4]]
===== JUnit 4 Support Classes

The `org.springframework.test.context.junit4` package provides the following support
classes for JUnit 4-based test cases (supported on JUnit 4.12 or higher):

* `AbstractJUnit4SpringContextTests`
* `AbstractTransactionalJUnit4SpringContextTests`

`AbstractJUnit4SpringContextTests` is an abstract base test class that integrates the
Spring TestContext Framework with explicit `ApplicationContext` testing support in a
JUnit 4 environment. When you extend `AbstractJUnit4SpringContextTests`, you can access a
`protected` `applicationContext` instance variable that you can use to perform explicit
bean lookups or to test the state of the context as a whole.

`AbstractTransactionalJUnit4SpringContextTests` is an abstract transactional extension of
`AbstractJUnit4SpringContextTests` that adds some convenience functionality for JDBC
access. This class expects a `javax.sql.DataSource` bean and a
`PlatformTransactionManager` bean to be defined in the `ApplicationContext`. When you
extend `AbstractTransactionalJUnit4SpringContextTests`, you can access a `protected`
`jdbcTemplate` instance variable that you can use to run SQL statements to query the
database. You can use such queries to confirm database state both before and after
running database-related application code, and Spring ensures that such queries run in
the scope of the same transaction as the application code. When used in conjunction with
an ORM tool, be sure to avoid <<testcontext-tx-false-positives, false positives>>.
As mentioned in <<integration-testing-support-jdbc>>,
`AbstractTransactionalJUnit4SpringContextTests` also provides convenience methods that
delegate to methods in `JdbcTestUtils` by using the aforementioned `jdbcTemplate`.
Furthermore, `AbstractTransactionalJUnit4SpringContextTests` provides an
`executeSqlScript(..)` method for running SQL scripts against the configured `DataSource`.

TIP: These classes are a convenience for extension. If you do not want your test classes
to be tied to a Spring-specific class hierarchy, you can configure your own custom test
classes by using `@RunWith(SpringRunner.class)` or <<testcontext-junit4-rules, Spring's
JUnit rules>>.

[[testcontext-junit-jupiter-extension]]
===== SpringExtension for JUnit Jupiter

The Spring TestContext Framework offers full integration with the JUnit Jupiter testing
framework, introduced in JUnit 5. By annotating test classes with
`@ExtendWith(SpringExtension.class)`, you can implement standard JUnit Jupiter-based unit
and integration tests and simultaneously reap the benefits of the TestContext framework,
such as support for loading application contexts, dependency injection of test instances,
transactional test method execution, and so on.

Furthermore, thanks to the rich extension API in JUnit Jupiter, Spring provides the
following features above and beyond the feature set that Spring supports for JUnit 4 and
TestNG:

* Dependency injection for test constructors, test methods, and test lifecycle callback
  methods. See <<testcontext-junit-jupiter-di>> for further details.
* Powerful support for link:https://junit.org/junit5/docs/current/user-guide/#extensions-conditions[conditional
  test execution] based on SpEL expressions, environment variables, system properties,
  and so on. See the documentation for `@EnabledIf` and `@DisabledIf` in
  <<integration-testing-annotations-junit-jupiter>> for further details and examples.
* Custom composed annotations that combine annotations from Spring and JUnit Jupiter. See
  the `@TransactionalDevTestConfig` and `@TransactionalIntegrationTest` examples in
  <<integration-testing-annotations-meta>> for further details.

The following code listing shows how to configure a test class to use the
`SpringExtension` in conjunction with `@ContextConfiguration`:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	// Instructs JUnit Jupiter to extend the test with Spring support.
	@ExtendWith(SpringExtension.class)
	// Instructs Spring to load an ApplicationContext from TestConfig.class
	@ContextConfiguration(classes = TestConfig.class)
	class SimpleTests {

		@Test
		void testMethod() {
			// execute test logic...
		}
	}
----

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	// Instructs JUnit Jupiter to extend the test with Spring support.
	@ExtendWith(SpringExtension::class)
	// Instructs Spring to load an ApplicationContext from TestConfig::class
	@ContextConfiguration(classes = [TestConfig::class])
	class SimpleTests {

		@Test
		fun testMethod() {
			// execute test logic...
		}
	}
----

Since you can also use annotations in JUnit 5 as meta-annotations, Spring provides the
`@SpringJUnitConfig` and `@SpringJUnitWebConfig` composed annotations to simplify the
configuration of the test `ApplicationContext` and JUnit Jupiter.

The following example uses `@SpringJUnitConfig` to reduce the amount of configuration
used in the previous example:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	// Instructs Spring to register the SpringExtension with JUnit
	// Jupiter and load an ApplicationContext from TestConfig.class
	@SpringJUnitConfig(TestConfig.class)
	class SimpleTests {

		@Test
		void testMethod() {
			// execute test logic...
		}
	}
----

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	// Instructs Spring to register the SpringExtension with JUnit
	// Jupiter and load an ApplicationContext from TestConfig.class
	@SpringJUnitConfig(TestConfig::class)
	class SimpleTests {

		@Test
		fun testMethod() {
			// execute test logic...
		}
	}
----

Similarly, the following example uses `@SpringJUnitWebConfig` to create a
`WebApplicationContext` for use with JUnit Jupiter:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	// Instructs Spring to register the SpringExtension with JUnit
	// Jupiter and load a WebApplicationContext from TestWebConfig.class
	@SpringJUnitWebConfig(TestWebConfig.class)
	class SimpleWebTests {

		@Test
		void testMethod() {
			// execute test logic...
		}
	}
----

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	// Instructs Spring to register the SpringExtension with JUnit
	// Jupiter and load a WebApplicationContext from TestWebConfig::class
	@SpringJUnitWebConfig(TestWebConfig::class)
	class SimpleWebTests {

		@Test
		fun testMethod() {
			// execute test logic...
		}
	}
----

See the documentation for `@SpringJUnitConfig` and `@SpringJUnitWebConfig` in
<<integration-testing-annotations-junit-jupiter>> for further details.

[[testcontext-junit-jupiter-di]]
===== Dependency Injection with `SpringExtension`

`SpringExtension` implements the
link:https://junit.org/junit5/docs/current/user-guide/#extensions-parameter-resolution[`ParameterResolver`]
extension API from JUnit Jupiter, which lets Spring provide dependency injection for test
constructors, test methods, and test lifecycle callback methods.

Specifically, `SpringExtension` can inject dependencies from the test's
`ApplicationContext` into test constructors and methods that are annotated with
`@BeforeAll`, `@AfterAll`, `@BeforeEach`, `@AfterEach`, `@Test`, `@RepeatedTest`,
`@ParameterizedTest`, and others.

[[testcontext-junit-jupiter-di-constructor]]
====== Constructor Injection

If a specific parameter in a constructor for a JUnit Jupiter test class is of type
`ApplicationContext` (or a sub-type thereof) or is annotated or meta-annotated with
`@Autowired`, `@Qualifier`, or `@Value`, Spring injects the value for that specific
parameter with the corresponding bean or value from the test's `ApplicationContext`.

Spring can also be configured to autowire all arguments for a test class constructor if
the constructor is considered to be _autowirable_. A constructor is considered to be
autowirable if one of the following conditions is met (in order of precedence).

* The constructor is annotated with `@Autowired`.
* `@TestConstructor` is present or meta-present on the test class with the `autowireMode`
  attribute set to `ALL`.
* The default _test constructor autowire mode_ has been changed to `ALL`.

See <<integration-testing-annotations-testconstructor>> for details on the use of
`@TestConstructor` and how to change the global _test constructor autowire mode_.

WARNING: If the constructor for a test class is considered to be _autowirable_, Spring
assumes the responsibility for resolving arguments for all parameters in the constructor.
Consequently, no other `ParameterResolver` registered with JUnit Jupiter can resolve
parameters for such a constructor.

[WARNING]
====
Constructor injection for test classes must not be used in conjunction with JUnit
Jupiter's `@TestInstance(PER_CLASS)` support if `@DirtiesContext` is used to close the
test's `ApplicationContext` before or after test methods.

The reason is that `@TestInstance(PER_CLASS)` instructs JUnit Jupiter to cache the test
instance between test method invocations. Consequently, the test instance will retain
references to beans that were originally injected from an `ApplicationContext` that has
been subsequently closed. Since the constructor for the test class will only be invoked
once in such scenarios, dependency injection will not occur again, and subsequent tests
will interact with beans from the closed `ApplicationContext` which may result in errors.

To use `@DirtiesContext` with "before test method" or "after test method" modes in
conjunction with `@TestInstance(PER_CLASS)`, one must configure dependencies from Spring
to be supplied via field or setter injection so that they can be re-injected between test
method invocations.
====

In the following example, Spring injects the `OrderService` bean from the
`ApplicationContext` loaded from `TestConfig.class` into the
`OrderServiceIntegrationTests` constructor.

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@SpringJUnitConfig(TestConfig.class)
	class OrderServiceIntegrationTests {

		private final OrderService orderService;

		@Autowired
		OrderServiceIntegrationTests(OrderService orderService) {
			this.orderService = orderService;
		}

		// tests that use the injected OrderService
	}
----

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@SpringJUnitConfig(TestConfig::class)
	class OrderServiceIntegrationTests @Autowired constructor(private val orderService: OrderService){
		// tests that use the injected OrderService
	}

----

Note that this feature lets test dependencies be `final` and therefore immutable.

If the `spring.test.constructor.autowire.mode` property is to `all` (see
<<integration-testing-annotations-testconstructor>>), we can omit the declaration of
`@Autowired` on the constructor in the previous example, resulting in the following.

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@SpringJUnitConfig(TestConfig.class)
	class OrderServiceIntegrationTests {

		private final OrderService orderService;

		OrderServiceIntegrationTests(OrderService orderService) {
			this.orderService = orderService;
		}

		// tests that use the injected OrderService
	}
----

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@SpringJUnitConfig(TestConfig::class)
	class OrderServiceIntegrationTests(val orderService:OrderService) {
		// tests that use the injected OrderService
	}
----

[[testcontext-junit-jupiter-di-method]]
====== Method Injection

If a parameter in a JUnit Jupiter test method or test lifecycle callback method is of
type `ApplicationContext` (or a sub-type thereof) or is annotated or meta-annotated with
`@Autowired`, `@Qualifier`, or `@Value`, Spring injects the value for that specific
parameter with the corresponding bean from the test's `ApplicationContext`.

In the following example, Spring injects the `OrderService` from the `ApplicationContext`
loaded from `TestConfig.class` into the `deleteOrder()` test method:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@SpringJUnitConfig(TestConfig.class)
	class OrderServiceIntegrationTests {

		@Test
		void deleteOrder(@Autowired OrderService orderService) {
			// use orderService from the test's ApplicationContext
		}
	}
----

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@SpringJUnitConfig(TestConfig::class)
	class OrderServiceIntegrationTests {

		@Test
		fun deleteOrder(@Autowired orderService: OrderService) {
			// use orderService from the test's ApplicationContext
		}
	}
----

Due to the robustness of the `ParameterResolver` support in JUnit Jupiter, you can also
have multiple dependencies injected into a single method, not only from Spring but also
from JUnit Jupiter itself or other third-party extensions.

The following example shows how to have both Spring and JUnit Jupiter inject dependencies
into the `placeOrderRepeatedly()` test method simultaneously.

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@SpringJUnitConfig(TestConfig.class)
	class OrderServiceIntegrationTests {

		@RepeatedTest(10)
		void placeOrderRepeatedly(RepetitionInfo repetitionInfo,
				@Autowired OrderService orderService) {

			// use orderService from the test's ApplicationContext
			// and repetitionInfo from JUnit Jupiter
		}
	}
----

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@SpringJUnitConfig(TestConfig::class)
	class OrderServiceIntegrationTests {

		@RepeatedTest(10)
		fun placeOrderRepeatedly(repetitionInfo:RepetitionInfo, @Autowired orderService:OrderService) {

			// use orderService from the test's ApplicationContext
			// and repetitionInfo from JUnit Jupiter
		}
	}
----

Note that the use of `@RepeatedTest` from JUnit Jupiter lets the test method gain access
to the `RepetitionInfo`.

[[testcontext-support-classes-testng]]
===== TestNG Support Classes

The `org.springframework.test.context.testng` package provides the following support
classes for TestNG based test cases:

* `AbstractTestNGSpringContextTests`
* `AbstractTransactionalTestNGSpringContextTests`

`AbstractTestNGSpringContextTests` is an abstract base test class that integrates the
Spring TestContext Framework with explicit `ApplicationContext` testing support in a
TestNG environment. When you extend `AbstractTestNGSpringContextTests`, you can access a
`protected` `applicationContext` instance variable that you can use to perform explicit
bean lookups or to test the state of the context as a whole.

`AbstractTransactionalTestNGSpringContextTests` is an abstract transactional extension of
`AbstractTestNGSpringContextTests` that adds some convenience functionality for JDBC
access. This class expects a `javax.sql.DataSource` bean and a
`PlatformTransactionManager` bean to be defined in the `ApplicationContext`. When you
extend `AbstractTransactionalTestNGSpringContextTests`, you can access a `protected`
`jdbcTemplate` instance variable that you can use to execute SQL statements to query the
database. You can use such queries to confirm database state both before and after
running database-related application code, and Spring ensures that such queries run in
the scope of the same transaction as the application code. When used in conjunction with
an ORM tool, be sure to avoid <<testcontext-tx-false-positives, false positives>>.
As mentioned in <<integration-testing-support-jdbc>>,
`AbstractTransactionalTestNGSpringContextTests` also provides convenience methods that
delegate to methods in `JdbcTestUtils` by using the aforementioned `jdbcTemplate`.
Furthermore, `AbstractTransactionalTestNGSpringContextTests` provides an
`executeSqlScript(..)` method for running SQL scripts against the configured `DataSource`.

TIP: These classes are a convenience for extension. If you do not want your test classes
to be tied to a Spring-specific class hierarchy, you can configure your own custom test
classes by using `@ContextConfiguration`, `@TestExecutionListeners`, and so on and by
manually instrumenting your test class with a `TestContextManager`. See the source code
of `AbstractTestNGSpringContextTests` for an example of how to instrument your test class.



[[spring-mvc-test-framework]]
=== Spring MVC Test Framework

The Spring MVC Test framework provides first class support for testing Spring MVC code
with a fluent API that you can use with JUnit, TestNG, or any other testing framework. It
is built on the {api-spring-framework}/mock/web/package-summary.html[Servlet API mock objects]
from the `spring-test` module and, hence, does not use a running Servlet container. It
uses the `DispatcherServlet` to provide full Spring MVC runtime behavior and provides
support for loading actual Spring configuration with the TestContext framework in
addition to a standalone mode, in which you can manually instantiate controllers and test
them one at a time.

Spring MVC Test also provides client-side support for testing code that uses the
`RestTemplate`. Client-side tests mock the server responses and also do not use a running
server.

TIP: Spring Boot provides an option to write full, end-to-end integration tests that
include a running server. If this is your goal, see the
{doc-spring-boot}/html/spring-boot-features.html#boot-features-testing[Spring Boot Reference Guide].
For more information on the differences between out-of-container and end-to-end
integration tests, see <<spring-mvc-test-vs-end-to-end-integration-tests>>.


[[spring-mvc-test-server]]
==== Server-Side Tests

You can write a plain unit test for a Spring MVC controller by using JUnit or TestNG. To
do so, instantiate the controller, inject it with mocked or stubbed dependencies, and
call its methods (passing `MockHttpServletRequest`, `MockHttpServletResponse`, and
others, as necessary). However, when writing such a unit test, much remains untested: for
example, request mappings, data binding, type conversion, validation, and much more.
Furthermore, other controller methods such as `@InitBinder`, `@ModelAttribute`, and
`@ExceptionHandler` may also be invoked as part of the request processing lifecycle.

The goal of Spring MVC Test is to provide an effective way to test controllers by
performing requests and generating responses through the actual `DispatcherServlet`.

Spring MVC Test builds on the familiar <<mock-objects-servlet, "`mock`" implementations of
the Servlet API>> available in the `spring-test` module. This allows performing requests
and generating responses without the need for running in a Servlet container. For the
most part, everything should work as it does at runtime with a few notable exceptions, as
explained in <<spring-mvc-test-vs-end-to-end-integration-tests>>. The following JUnit
Jupiter-based example uses Spring MVC Test:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.*;
	import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.*;

	@SpringJUnitWebConfig(locations = "test-servlet-context.xml")
	class ExampleTests {

		MockMvc mockMvc;

		@BeforeEach
		void setup(WebApplicationContext wac) {
			this.mockMvc = MockMvcBuilders.webAppContextSetup(wac).build();
		}

		@Test
		void getAccount() throws Exception {
			this.mockMvc.perform(get("/accounts/1")
					.accept(MediaType.APPLICATION_JSON))
				.andExpect(status().isOk())
				.andExpect(content().contentType("application/json"))
				.andExpect(jsonPath("$.name").value("Lee"));
		}
	}
----
[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	import org.springframework.test.web.servlet.get

	@SpringJUnitWebConfig(locations = ["test-servlet-context.xml"])
	class ExampleTests {

		lateinit var mockMvc: MockMvc

		@BeforeEach
		fun setup(wac: WebApplicationContext) {
			this.mockMvc = MockMvcBuilders.webAppContextSetup(wac).build()
		}

		@Test
		fun getAccount() {
			mockMvc.get("/accounts/1") {
				accept = MediaType.APPLICATION_JSON
			}.andExpect {
				status { isOk }
				content { contentType(MediaType.APPLICATION_JSON) }
				jsonPath("$.name") { value("Lee") }
			}
		}
	}
----

NOTE: A dedicated <<languages.adoc#mockmvc-dsl, MockMvc DSL>> is available in Kotlin

The preceding test relies on the `WebApplicationContext` support of the TestContext
framework to load Spring configuration from an XML configuration file located in the same
package as the test class, but Java-based and Groovy-based configuration are also
supported. See these
https://github.com/spring-projects/spring-framework/tree/master/spring-test/src/test/java/org/springframework/test/web/servlet/samples/context[sample tests].

The `MockMvc` instance is used to perform a `GET` request to `/accounts/1` and verify
that the resulting response has status 200, the content type is `application/json`, and
the response body has a JSON property called `name` with the value `Lee`. The `jsonPath`
syntax is supported through the Jayway https://github.com/jayway/JsonPath[JsonPath
project]. Many other options for verifying the result of the performed request are
discussed later in this document.

[[spring-mvc-test-server-static-imports]]
===== Static Imports

The fluent API in the example from the <<spring-mvc-test-server, preceding section>>
requires a few static imports, such as `MockMvcRequestBuilders.{asterisk}`,
`MockMvcResultMatchers.{asterisk}`, and `MockMvcBuilders.{asterisk}`. An easy way to find
these classes is to search for types that match `MockMvc*`. If you use Eclipse or the
Eclipse-based Spring Tool Suite, be sure to add them as "`favorite static members`" in
the Eclipse preferences under Java -> Editor -> Content Assist -> Favorites. Doing so
lets you use content assist after typing the first character of the static method name.
Other IDEs (such as IntelliJ) may not require any additional configuration. Check the
support for code completion on static members.

[[spring-mvc-test-server-setup-options]]
===== Setup Choices

You have two main options for creating an instance of `MockMvc`. The first is to load
Spring MVC configuration through the TestContext framework, which loads the Spring
configuration and injects a `WebApplicationContext` into the test to use to build a
`MockMvc` instance. The following example shows how to do so:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@SpringJUnitWebConfig(locations = "my-servlet-context.xml")
	class MyWebTests {

		MockMvc mockMvc;

		@BeforeEach
		void setup(WebApplicationContext wac) {
			this.mockMvc = MockMvcBuilders.webAppContextSetup(this.wac).build();
		}

		// ...

	}
----

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@SpringJUnitWebConfig(locations = ["my-servlet-context.xml"])
	class MyWebTests {

		lateinit var mockMvc: MockMvc

		@BeforeEach
		fun setup(wac: WebApplicationContext) {
			mockMvc = MockMvcBuilders.webAppContextSetup(wac).build()
		}

		// ...

	}
----

Your second option is to manually create a controller instance without loading Spring
configuration. Instead, basic default configuration, roughly comparable to that of the
MVC JavaConfig or the MVC namespace, is automatically created. You can customize it to a
degree. The following example shows how to do so:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	class MyWebTests {

		MockMvc mockMvc;

		@BeforeEach
		void setup() {
			this.mockMvc = MockMvcBuilders.standaloneSetup(new AccountController()).build();
		}

		// ...

	}
----

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	class MyWebTests {

		lateinit var mockMvc : MockMvc

		@BeforeEach
		fun setup() {
			mockMvc = MockMvcBuilders.standaloneSetup(AccountController()).build()
		}

		// ...

	}
----

Which setup option should you use?

The `webAppContextSetup` loads your actual Spring MVC configuration, resulting in a more
complete integration test. Since the TestContext framework caches the loaded Spring
configuration, it helps keep tests running fast, even as you introduce more tests in your
test suite. Furthermore, you can inject mock services into controllers through Spring
configuration to remain focused on testing the web layer. The following example declares
a mock service with Mockito:

[source,xml,indent=0,subs="verbatim,quotes"]
----
	<bean id="accountService" class="org.mockito.Mockito" factory-method="mock">
		<constructor-arg value="org.example.AccountService"/>
	</bean>
----

You can then inject the mock service into the test to set up and verify your
expectations, as the following example shows:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@SpringJUnitWebConfig(locations = "test-servlet-context.xml")
	class AccountTests {

		@Autowired
		AccountService accountService;

		MockMvc mockMvc;

		@BeforeEach
		void setup(WebApplicationContext wac) {
			this.mockMvc = MockMvcBuilders.webAppContextSetup(wac).build();
		}

		// ...

	}
----
[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@SpringJUnitWebConfig(locations = ["test-servlet-context.xml"])
	class AccountTests {

		@Autowired
		lateinit var accountService: AccountService

		lateinit mockMvc: MockMvc

		@BeforeEach
		fun setup(wac: WebApplicationContext) {
			mockMvc = MockMvcBuilders.webAppContextSetup(wac).build()
		}

		// ...

	}
----

The `standaloneSetup`, on the other hand, is a little closer to a unit test. It tests one
controller at a time. You can manually inject the controller with mock dependencies, and
it does not involve loading Spring configuration. Such tests are more focused on style
and make it easier to see which controller is being tested, whether any specific Spring
MVC configuration is required to work, and so on. The `standaloneSetup` is also a very
convenient way to write ad-hoc tests to verify specific behavior or to debug an issue.

As with most "`integration versus unit testing`" debates, there is no right or wrong
answer. However, using the `standaloneSetup` does imply the need for additional
`webAppContextSetup` tests in order to verify your Spring MVC configuration.
Alternatively, you can write all your tests with `webAppContextSetup`, in order to always
test against your actual Spring MVC configuration.

[[spring-mvc-test-server-setup-steps]]
===== Setup Features

No matter which MockMvc builder you use, all `MockMvcBuilder` implementations provide
some common and very useful features. For example, you can declare an `Accept` header for
all requests and expect a status of 200 as well as a `Content-Type` header in all
responses, as follows:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	// static import of MockMvcBuilders.standaloneSetup

	MockMvc mockMvc = standaloneSetup(new MusicController())
		.defaultRequest(get("/").accept(MediaType.APPLICATION_JSON))
		.alwaysExpect(status().isOk())
		.alwaysExpect(content().contentType("application/json;charset=UTF-8"))
		.build();
----

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	// Not possible in Kotlin until https://youtrack.jetbrains.com/issue/KT-22208 is fixed
----

In addition, third-party frameworks (and applications) can pre-package setup
instructions, such as those in a `MockMvcConfigurer`. The Spring Framework has one such
built-in implementation that helps to save and re-use the HTTP session across requests.
You can use it as follows:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	// static import of SharedHttpSessionConfigurer.sharedHttpSession

	MockMvc mockMvc = MockMvcBuilders.standaloneSetup(new TestController())
			.apply(sharedHttpSession())
			.build();

	// Use mockMvc to perform requests...
----

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	// Not possible in Kotlin until https://youtrack.jetbrains.com/issue/KT-22208 is fixed
----

See the javadoc for
{api-spring-framework}/test/web/servlet/setup/ConfigurableMockMvcBuilder.html[`ConfigurableMockMvcBuilder`]
for a list of all MockMvc builder features or use the IDE to explore the available options.

[[spring-mvc-test-server-performing-requests]]
===== Performing Requests

You can perform requests that use any HTTP method, as the following example shows:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	mockMvc.perform(post("/hotels/{id}", 42).accept(MediaType.APPLICATION_JSON));
----

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	import org.springframework.test.web.servlet.post

	mockMvc.post("/hotels/{id}", 42) {
		accept = MediaType.APPLICATION_JSON
	}
----

You can also perform file upload requests that internally use
`MockMultipartHttpServletRequest` so that there is no actual parsing of a multipart
request. Rather, you have to set it up to be similar to the following example:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	mockMvc.perform(multipart("/doc").file("a1", "ABC".getBytes("UTF-8")));
----

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	import org.springframework.test.web.servlet.multipart

	mockMvc.multipart("/doc") {
		file("a1", "ABC".toByteArray(charset("UTF8")))
	}
----

You can specify query parameters in URI template style, as the following example shows:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	mockMvc.perform(get("/hotels?thing={thing}", "somewhere"));
----
[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	mockMvc.get("/hotels?thing={thing}", "somewhere")
----

You can also add Servlet request parameters that represent either query or form
parameters, as the following example shows:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	mockMvc.perform(get("/hotels").param("thing", "somewhere"));
----
[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	import org.springframework.test.web.servlet.get

	mockMvc.get("/hotels") {
		param("thing", "somewhere")
	}
----

If application code relies on Servlet request parameters and does not check the query
string explicitly (as is most often the case), it does not matter which option you use.
Keep in mind, however, that query parameters provided with the URI template are decoded
while request parameters provided through the `param(...)` method are expected to already
be decoded.

In most cases, it is preferable to leave the context path and the Servlet path out of the
request URI. If you must test with the full request URI, be sure to set the `contextPath`
and `servletPath` accordingly so that request mappings work, as the following example
shows:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	mockMvc.perform(get("/app/main/hotels/{id}").contextPath("/app").servletPath("/main"))
----
[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	import org.springframework.test.web.servlet.get

	mockMvc.get("/app/main/hotels/{id}") {
		contextPath = "/app"
		servletPath = "/main"
	}
----

In the preceding example, it would be cumbersome to set the `contextPath` and
`servletPath` with every performed request. Instead, you can set up default request
properties, as the following example shows:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	class MyWebTests {

		MockMvc mockMvc;

		@BeforeEach
		void setup() {
			mockMvc = standaloneSetup(new AccountController())
				.defaultRequest(get("/")
				.contextPath("/app").servletPath("/main")
				.accept(MediaType.APPLICATION_JSON)).build();
		}
	}
----
[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	// Not possible in Kotlin until https://youtrack.jetbrains.com/issue/KT-22208 is fixed
----

The preceding properties affect every request performed through the `MockMvc` instance.
If the same property is also specified on a given request, it overrides the default
value. That is why the HTTP method and URI in the default request do not matter, since
they must be specified on every request.

[[spring-mvc-test-server-defining-expectations]]
===== Defining Expectations

You can define expectations by appending one or more `.andExpect(..)` calls after
performing a request, as the following example shows:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	mockMvc.perform(get("/accounts/1")).andExpect(status().isOk());
----

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	import org.springframework.test.web.servlet.get

	mockMvc.get("/accounts/1").andExpect {
		status().isOk()
	}
----

`MockMvcResultMatchers.*` provides a number of expectations, some of which are further
nested with more detailed expectations.

Expectations fall in two general categories. The first category of assertions verifies
properties of the response (for example, the response status, headers, and content).
These are the most important results to assert.

The second category of assertions goes beyond the response. These assertions let you
inspect Spring MVC specific aspects, such as which controller method processed the
request, whether an exception was raised and handled, what the content of the model is,
what view was selected, what flash attributes were added, and so on. They also let you
inspect Servlet specific aspects, such as request and session attributes.

The following test asserts that binding or validation failed:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	mockMvc.perform(post("/persons"))
		.andExpect(status().isOk())
		.andExpect(model().attributeHasErrors("person"));
----

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	import org.springframework.test.web.servlet.post

	mockMvc.post("/persons").andExpect {
		status().isOk()
		model {
			attributeHasErrors("person")
		}
	}
----

Many times, when writing tests, it is useful to dump the results of the performed
request. You can do so as follows, where `print()` is a static import from
`MockMvcResultHandlers`:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	mockMvc.perform(post("/persons"))
		.andDo(print())
		.andExpect(status().isOk())
		.andExpect(model().attributeHasErrors("person"));
----

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	import org.springframework.test.web.servlet.post

	mockMvc.post("/persons").andDo {
			print()
		}.andExpect {
			status().isOk()
			model {
				attributeHasErrors("person")
			}
		}
----

As long as request processing does not cause an unhandled exception, the `print()` method
prints all the available result data to `System.out`. There is also a `log()` method and
two additional variants of the `print()` method, one that accepts an `OutputStream` and
one that accepts a `Writer`. For example, invoking `print(System.err)` prints the result
data to `System.err`, while invoking `print(myWriter)` prints the result data to a custom
writer. If you want to have the result data logged instead of printed, you can invoke the
`log()` method, which logs the result data as a single `DEBUG` message under the
`org.springframework.test.web.servlet.result` logging category.

In some cases, you may want to get direct access to the result and verify something that
cannot be verified otherwise. This can be achieved by appending `.andReturn()` after all
other expectations, as the following example shows:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	MvcResult mvcResult = mockMvc.perform(post("/persons")).andExpect(status().isOk()).andReturn();
	// ...
----

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	var mvcResult = mockMvc.post("/persons").andExpect { status().isOk() }.andReturn()
	// ...
----

If all tests repeat the same expectations, you can set up common expectations once when
building the `MockMvc` instance, as the following example shows:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	standaloneSetup(new SimpleController())
		.alwaysExpect(status().isOk())
		.alwaysExpect(content().contentType("application/json;charset=UTF-8"))
		.build()
----
[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	// Not possible in Kotlin until https://youtrack.jetbrains.com/issue/KT-22208 is fixed
----

Note that common expectations are always applied and cannot be overridden without
creating a separate `MockMvc` instance.

When a JSON response content contains hypermedia links created with
https://github.com/spring-projects/spring-hateoas[Spring HATEOAS], you can verify the
resulting links by using JsonPath expressions, as the following example shows:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	mockMvc.perform(get("/people").accept(MediaType.APPLICATION_JSON))
		.andExpect(jsonPath("$.links[?(@.rel == 'self')].href").value("http://localhost:8080/people"));
----

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	mockMvc.get("/people") {
		accept(MediaType.APPLICATION_JSON)
	}.andExpect {
		jsonPath("$.links[?(@.rel == 'self')].href") {
			value("http://localhost:8080/people")
		}
	}
----

When XML response content contains hypermedia links created with
https://github.com/spring-projects/spring-hateoas[Spring HATEOAS], you can verify the
resulting links by using XPath expressions:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	Map<String, String> ns = Collections.singletonMap("ns", "http://www.w3.org/2005/Atom");
	mockMvc.perform(get("/handle").accept(MediaType.APPLICATION_XML))
		.andExpect(xpath("/person/ns:link[@rel='self']/@href", ns).string("http://localhost:8080/people"));
----

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	val ns = mapOf("ns" to "http://www.w3.org/2005/Atom")
	mockMvc.get("/handle") {
		accept(MediaType.APPLICATION_XML)
	}.andExpect {
		xpath("/person/ns:link[@rel='self']/@href", ns) {
			string("http://localhost:8080/people")
		}
	}
----

[[spring-mvc-test-async-requests]]
===== Async Requests

Servlet 3.0 asynchronous requests,
<<web.adoc#mvc-ann-async,supported in Spring MVC>>, work by exiting the Servlet container
thread and allowing the application to compute the response asynchronously, after which
an async dispatch is made to complete processing on a Servlet container thread.

In Spring MVC Test, async requests can be tested by asserting the produced async value
first, then manually performing the async dispatch, and finally verifying the response.
Below is an example test for controller methods that return `DeferredResult`, `Callable`,
or reactive type such as Reactor `Mono`:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@Test
	void test() throws Exception {
        MvcResult mvcResult = this.mockMvc.perform(get("/path"))
                .andExpect(status().isOk()) <1>
                .andExpect(request().asyncStarted()) <2>
                .andExpect(request().asyncResult("body")) <3>
                .andReturn();

        this.mockMvc.perform(asyncDispatch(mvcResult)) <4>
                .andExpect(status().isOk()) <5>
                .andExpect(content().string("body"));
    }
----
<1> Check response status is still unchanged
<2> Async processing must have started
<3> Wait and assert the async result
<4> Manually perform an ASYNC dispatch (as there is no running container)
<5> Verify the final response

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@Test
	fun test() {
		var mvcResult = mockMvc.get("/path").andExpect {
			status().isOk() // <1>
			request { asyncStarted() } // <2>
			// TODO Remove unused generic parameter
			request { asyncResult<Nothing>("body") } // <3>
		}.andReturn()


		mockMvc.perform(asyncDispatch(mvcResult)) // <4>
				.andExpect {
					status().isOk() // <5>
					content().string("body")
				}
	}
----
<1> Check response status is still unchanged
<2> Async processing must have started
<3> Wait and assert the async result
<4> Manually perform an ASYNC dispatch (as there is no running container)
<5> Verify the final response


[[spring-mvc-test-vs-streaming-response]]
===== Streaming Responses

There are no options built into Spring MVC Test for container-less testing of streaming
responses. Applications that make use of
<<web.adoc#mvc-ann-async-http-streaming,Spring MVC streaming>> options can use the
<<testing.adoc#webtestclient-stream,WebTestClient>> to perform end-to-end, integration
tests against a running server. This is also supported in Spring Boot where you can
{doc-spring-boot}/html/spring-boot-features.html#boot-features-testing-spring-boot-applications-testing-with-running-server[test a running server]
with `WebTestClient`. One extra advantage is the ability to use the `StepVerifier` from
project Reactor that allows declaring expectations on a stream of data.


[[spring-mvc-test-server-filters]]
===== Filter Registrations

When setting up a `MockMvc` instance, you can register one or more Servlet `Filter`
instances, as the following example shows:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	mockMvc = standaloneSetup(new PersonController()).addFilters(new CharacterEncodingFilter()).build();
----
[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	// Not possible in Kotlin until https://youtrack.jetbrains.com/issue/KT-22208 is fixed
----

Registered filters are invoked through the `MockFilterChain` from `spring-test`, and the
last filter delegates to the `DispatcherServlet`.


[[spring-mvc-test-vs-end-to-end-integration-tests]]
===== Spring MVC Test vs End-to-End Tests

Spring MVC Test is built on Servlet API mock implementations from the
`spring-test` module and does not rely on a running container. Therefore, there are
some differences when compared to full end-to-end integration tests with an actual
client and a live server running.

The easiest way to think about this is by starting with a blank `MockHttpServletRequest`.
Whatever you add to it is what the request becomes. Things that may catch you by surprise
are that there is no context path by default; no `jsessionid` cookie; no forwarding,
error, or async dispatches; and, therefore, no actual JSP rendering. Instead,
"`forwarded`" and "`redirected`" URLs are saved in the `MockHttpServletResponse` and can
be asserted with expectations.

This means that, if you use JSPs, you can verify the JSP page to which the request was
forwarded, but no HTML is rendered. In other words, the JSP is not invoked. Note,
however, that all other rendering technologies that do not rely on forwarding, such as
Thymeleaf and Freemarker, render HTML to the response body as expected. The same is true
for rendering JSON, XML, and other formats through `@ResponseBody` methods.

Alternatively, you may consider the full end-to-end integration testing support from
Spring Boot with `@SpringBootTest`. See the
{doc-spring-boot}/html/spring-boot-features.html#boot-features-testing[Spring Boot Reference Guide].

There are pros and cons for each approach. The options provided in Spring MVC Test are
different stops on the scale from classic unit testing to full integration testing. To be
certain, none of the options in Spring MVC Test fall under the category of classic unit
testing, but they are a little closer to it. For example, you can isolate the web layer
by injecting mocked services into controllers, in which case you are testing the web
layer only through the `DispatcherServlet` but with actual Spring configuration, as you
might test the data access layer in isolation from the layers above it. Also, you can use
the stand-alone setup, focusing on one controller at a time and manually providing the
configuration required to make it work.

Another important distinction when using Spring MVC Test is that, conceptually, such
tests are the server-side, so you can check what handler was used, if an exception was
handled with a HandlerExceptionResolver, what the content of the model is, what binding
errors there were, and other details. That means that it is easier to write expectations,
since the server is not a black box, as it is when testing it through an actual HTTP
client. This is generally an advantage of classic unit testing: It is easier to write,
reason about, and debug but does not replace the need for full integration tests. At the
same time, it is important not to lose sight of the fact that the response is the most
important thing to check. In short, there is room here for multiple styles and strategies
of testing even within the same project.

[[spring-mvc-test-server-resources]]
===== Further Examples

The framework's own tests include
https://github.com/spring-projects/spring-framework/tree/master/spring-test/src/test/java/org/springframework/test/web/servlet/samples[many
sample tests] intended to show how to use Spring MVC Test. You can browse these examples
for further ideas. Also, the
https://github.com/spring-projects/spring-mvc-showcase[`spring-mvc-showcase`] project has
full test coverage based on Spring MVC Test.


[[spring-mvc-test-server-htmlunit]]
==== HtmlUnit Integration

Spring provides integration between <<spring-mvc-test-server, MockMvc>> and
http://htmlunit.sourceforge.net/[HtmlUnit]. This simplifies performing end-to-end testing
when using HTML-based views. This integration lets you:

* Easily test HTML pages by using tools such as
  http://htmlunit.sourceforge.net/[HtmlUnit],
  https://www.seleniumhq.org[WebDriver], and
  http://www.gebish.org/manual/current/#spock-junit-testng[Geb] without the need to
  deploy to a Servlet container.
* Test JavaScript within pages.
* Optionally, test using mock services to speed up testing.
* Share logic between in-container end-to-end tests and out-of-container integration tests.

NOTE: MockMvc works with templating technologies that do not rely on a Servlet Container
(for example, Thymeleaf, FreeMarker, and others), but it does not work with JSPs, since
they rely on the Servlet container.

[[spring-mvc-test-server-htmlunit-why]]
===== Why HtmlUnit Integration?

The most obvious question that comes to mind is "`Why do I need this?`" The answer is
best found by exploring a very basic sample application. Assume you have a Spring MVC web
application that supports CRUD operations on a `Message` object. The application also
supports paging through all messages. How would you go about testing it?

With Spring MVC Test, we can easily test if we are able to create a `Message`, as follows:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	MockHttpServletRequestBuilder createMessage = post("/messages/")
			.param("summary", "Spring Rocks")
			.param("text", "In case you didn't know, Spring Rocks!");

	mockMvc.perform(createMessage)
			.andExpect(status().is3xxRedirection())
			.andExpect(redirectedUrl("/messages/123"));
----
[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@Test
	fun test() {
		mockMvc.post("/messages/") {
			param("summary", "Spring Rocks")
			param("text", "In case you didn't know, Spring Rocks!")
		}.andExpect {
			status().is3xxRedirection()
			redirectedUrl("/messages/123")
		}
	}
----

What if we want to test the form view that lets us create the message? For example,
assume our form looks like the following snippet:

[source,xml,indent=0]
----
	<form id="messageForm" action="/messages/" method="post">
		<div class="pull-right"><a href="/messages/">Messages</a></div>

		<label for="summary">Summary</label>
		<input type="text" class="required" id="summary" name="summary" value="" />

		<label for="text">Message</label>
		<textarea id="text" name="text"></textarea>

		<div class="form-actions">
			<input type="submit" value="Create" />
		</div>
	</form>
----

How do we ensure that our form produce the correct request to create a new message? A
naive attempt might resemble the following:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	mockMvc.perform(get("/messages/form"))
			.andExpect(xpath("//input[@name='summary']").exists())
			.andExpect(xpath("//textarea[@name='text']").exists());
----

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	mockMvc.get("/messages/form").andExpect {
		xpath("//input[@name='summary']") { exists() }
		xpath("//textarea[@name='text']") { exists() }
	}
----

This test has some obvious drawbacks. If we update our controller to use the parameter
`message` instead of `text`, our form test continues to pass, even though the HTML form
is out of synch with the controller. To resolve this we can combine our two tests, as
follows:

[[spring-mvc-test-server-htmlunit-mock-mvc-test]]
[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	String summaryParamName = "summary";
	String textParamName = "text";
	mockMvc.perform(get("/messages/form"))
			.andExpect(xpath("//input[@name='" + summaryParamName + "']").exists())
			.andExpect(xpath("//textarea[@name='" + textParamName + "']").exists());

	MockHttpServletRequestBuilder createMessage = post("/messages/")
			.param(summaryParamName, "Spring Rocks")
			.param(textParamName, "In case you didn't know, Spring Rocks!");

	mockMvc.perform(createMessage)
			.andExpect(status().is3xxRedirection())
			.andExpect(redirectedUrl("/messages/123"));
----

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	val summaryParamName = "summary";
	val textParamName = "text";
	mockMvc.get("/messages/form").andExpect {
		xpath("//input[@name='$summaryParamName']") { exists() }
		xpath("//textarea[@name='$textParamName']") { exists() }
	}
	mockMvc.post("/messages/") {
		param(summaryParamName, "Spring Rocks")
		param(textParamName, "In case you didn't know, Spring Rocks!")
	}.andExpect {
		status().is3xxRedirection()
		redirectedUrl("/messages/123")
	}
----

This would reduce the risk of our test incorrectly passing, but there are still some
problems:

* What if we have multiple forms on our page? Admittedly, we could update our XPath
  expressions, but they get more complicated as we take more factors into account: Are
  the fields the correct type? Are the fields enabled? And so on.
* Another issue is that we are doing double the work we would expect. We must first
  verify the view, and then we submit the view with the same parameters we just verified.
  Ideally, this could be done all at once.
* Finally, we still cannot account for some things. For example, what if the form has
  JavaScript validation that we wish to test as well?

The overall problem is that testing a web page does not involve a single interaction.
Instead, it is a combination of how the user interacts with a web page and how that web
page interacts with other resources. For example, the result of a form view is used as
the input to a user for creating a message. In addition, our form view can potentially
use additional resources that impact the behavior of the page, such as JavaScript
validation.

[[spring-mvc-test-server-htmlunit-why-integration]]
====== Integration Testing to the Rescue?

To resolve the issues mentioned earlier, we could perform end-to-end integration testing,
but this has some drawbacks. Consider testing the view that lets us page through the
messages. We might need the following tests:

* Does our page display a notification to the user to indicate that no results are
  available when the messages are empty?
* Does our page properly display a single message?
* Does our page properly support paging?

To set up these tests, we need to ensure our database contains the proper messages. This
leads to a number of additional challenges:

* Ensuring the proper messages are in the database can be tedious. (Consider foreign key
  constraints.)
* Testing can become slow, since each test would need to ensure that the database is in
  the correct state.
* Since our database needs to be in a specific state, we cannot run tests in parallel.
* Performing assertions on such items as auto-generated ids, timestamps, and others can
  be difficult.

These challenges do not mean that we should abandon end-to-end integration testing
altogether. Instead, we can reduce the number of end-to-end integration tests by
refactoring our detailed tests to use mock services that run much faster, more reliably,
and without side effects. We can then implement a small number of true end-to-end
integration tests that validate simple workflows to ensure that everything works together
properly.

[[spring-mvc-test-server-htmlunit-why-mockmvc]]
====== Enter HtmlUnit Integration

So how can we achieve a balance between testing the interactions of our pages and still
retain good performance within our test suite? The answer is: "`By integrating MockMvc
with HtmlUnit.`"

[[spring-mvc-test-server-htmlunit-options]]
====== HtmlUnit Integration Options

You have a number of options when you want to integrate MockMvc with HtmlUnit:

* <<spring-mvc-test-server-htmlunit-mah,MockMvc and HtmlUnit>>: Use this option if you
  want to use the raw HtmlUnit libraries.
* <<spring-mvc-test-server-htmlunit-webdriver,MockMvc and WebDriver>>: Use this option to
  ease development and reuse code between integration and end-to-end testing.
* <<spring-mvc-test-server-htmlunit-geb,MockMvc and Geb>>: Use this option if you want to
  use Groovy for testing, ease development, and reuse code between integration and
  end-to-end testing.

[[spring-mvc-test-server-htmlunit-mah]]
===== MockMvc and HtmlUnit

This section describes how to integrate MockMvc and HtmlUnit. Use this option if you want
to use the raw HtmlUnit libraries.

[[spring-mvc-test-server-htmlunit-mah-setup]]
====== MockMvc and HtmlUnit Setup

First, make sure that you have included a test dependency on
`net.sourceforge.htmlunit:htmlunit`. In order to use HtmlUnit with Apache HttpComponents
4.5+, you need to use HtmlUnit 2.18 or higher.

We can easily create an HtmlUnit `WebClient` that integrates with MockMvc by using the
`MockMvcWebClientBuilder`, as follows:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	WebClient webClient;

	@BeforeEach
	void setup(WebApplicationContext context) {
		webClient = MockMvcWebClientBuilder
				.webAppContextSetup(context)
				.build();
	}
----

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	lateinit var webClient: WebClient

	@BeforeEach
	fun setup(context: WebApplicationContext) {
		webClient = MockMvcWebClientBuilder
				.webAppContextSetup(context)
				.build()
	}
----

NOTE: This is a simple example of using `MockMvcWebClientBuilder`. For advanced usage,
see <<spring-mvc-test-server-htmlunit-mah-advanced-builder>>.

This ensures that any URL that references `localhost` as the server is directed to our
`MockMvc` instance without the need for a real HTTP connection. Any other URL is
requested by using a network connection, as normal. This lets us easily test the use of
CDNs.

[[spring-mvc-test-server-htmlunit-mah-usage]]
====== MockMvc and HtmlUnit Usage

Now we can use HtmlUnit as we normally would but without the need to deploy our
application to a Servlet container. For example, we can request the view to create a
message with the following:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	HtmlPage createMsgFormPage = webClient.getPage("http://localhost/messages/form");
----

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	val createMsgFormPage = webClient.getPage("http://localhost/messages/form")
----

NOTE: The default context path is `""`. Alternatively, we can specify the context path,
as described in <<spring-mvc-test-server-htmlunit-mah-advanced-builder>>.

Once we have a reference to the `HtmlPage`, we can then fill out the form and submit it
to create a message, as the following example shows:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	HtmlForm form = createMsgFormPage.getHtmlElementById("messageForm");
	HtmlTextInput summaryInput = createMsgFormPage.getHtmlElementById("summary");
	summaryInput.setValueAttribute("Spring Rocks");
	HtmlTextArea textInput = createMsgFormPage.getHtmlElementById("text");
	textInput.setText("In case you didn't know, Spring Rocks!");
	HtmlSubmitInput submit = form.getOneHtmlElementByAttribute("input", "type", "submit");
	HtmlPage newMessagePage = submit.click();
----
[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	val form = createMsgFormPage.getHtmlElementById("messageForm")
	val summaryInput = createMsgFormPage.getHtmlElementById("summary")
	summaryInput.setValueAttribute("Spring Rocks")
	val textInput = createMsgFormPage.getHtmlElementById("text")
	textInput.setText("In case you didn't know, Spring Rocks!")
	val submit = form.getOneHtmlElementByAttribute("input", "type", "submit")
	val newMessagePage = submit.click()
----

Finally, we can verify that a new message was created successfully. The following
assertions use the https://joel-costigliola.github.io/assertj/[AssertJ] library:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	assertThat(newMessagePage.getUrl().toString()).endsWith("/messages/123");
	String id = newMessagePage.getHtmlElementById("id").getTextContent();
	assertThat(id).isEqualTo("123");
	String summary = newMessagePage.getHtmlElementById("summary").getTextContent();
	assertThat(summary).isEqualTo("Spring Rocks");
	String text = newMessagePage.getHtmlElementById("text").getTextContent();
	assertThat(text).isEqualTo("In case you didn't know, Spring Rocks!");
----
[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	assertThat(newMessagePage.getUrl().toString()).endsWith("/messages/123")
	val id = newMessagePage.getHtmlElementById("id").getTextContent()
	assertThat(id).isEqualTo("123")
	val summary = newMessagePage.getHtmlElementById("summary").getTextContent()
	assertThat(summary).isEqualTo("Spring Rocks")
	val text = newMessagePage.getHtmlElementById("text").getTextContent()
	assertThat(text).isEqualTo("In case you didn't know, Spring Rocks!")
----

The preceding code improves on our
<<spring-mvc-test-server-htmlunit-mock-mvc-test, MockMvc test>> in a number of ways.
First, we no longer have to explicitly verify our form and then create a request that
looks like the form. Instead, we request the form, fill it out, and submit it, thereby
significantly reducing the overhead.

Another important factor is that http://htmlunit.sourceforge.net/javascript.html[HtmlUnit
uses the Mozilla Rhino engine] to evaluate JavaScript. This means that we can also test
the behavior of JavaScript within our pages.

See the http://htmlunit.sourceforge.net/gettingStarted.html[HtmlUnit documentation] for
additional information about using HtmlUnit.

[[spring-mvc-test-server-htmlunit-mah-advanced-builder]]
====== Advanced `MockMvcWebClientBuilder`

In the examples so far, we have used `MockMvcWebClientBuilder` in the simplest way
possible, by building a `WebClient` based on the `WebApplicationContext` loaded for us by
the Spring TestContext Framework. This approach is repeated in the following example:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	WebClient webClient;

	@BeforeEach
	void setup(WebApplicationContext context) {
		webClient = MockMvcWebClientBuilder
				.webAppContextSetup(context)
				.build();
	}
----

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	lateinit var webClient: WebClient

	@BeforeEach
	fun setup(context: WebApplicationContext) {
		webClient = MockMvcWebClientBuilder
				.webAppContextSetup(context)
				.build()
	}
----

We can also specify additional configuration options, as the following example shows:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	WebClient webClient;

	@BeforeEach
	void setup() {
		webClient = MockMvcWebClientBuilder
			// demonstrates applying a MockMvcConfigurer (Spring Security)
			.webAppContextSetup(context, springSecurity())
			// for illustration only - defaults to ""
			.contextPath("")
			// By default MockMvc is used for localhost only;
			// the following will use MockMvc for example.com and example.org as well
			.useMockMvcForHosts("example.com","example.org")
			.build();
	}
----
[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	lateinit var webClient: WebClient

	@BeforeEach
	fun setup() {
		webClient = MockMvcWebClientBuilder
			// demonstrates applying a MockMvcConfigurer (Spring Security)
			.webAppContextSetup(context, springSecurity())
			// for illustration only - defaults to ""
			.contextPath("")
			// By default MockMvc is used for localhost only;
			// the following will use MockMvc for example.com and example.org as well
			.useMockMvcForHosts("example.com","example.org")
			.build()
	}
----

As an alternative, we can perform the exact same setup by configuring the `MockMvc`
instance separately and supplying it to the `MockMvcWebClientBuilder`, as follows:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	MockMvc mockMvc = MockMvcBuilders
			.webAppContextSetup(context)
			.apply(springSecurity())
			.build();

	webClient = MockMvcWebClientBuilder
			.mockMvcSetup(mockMvc)
			// for illustration only - defaults to ""
			.contextPath("")
			// By default MockMvc is used for localhost only;
			// the following will use MockMvc for example.com and example.org as well
			.useMockMvcForHosts("example.com","example.org")
			.build();
----

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	// Not possible in Kotlin until https://youtrack.jetbrains.com/issue/KT-22208 is fixed
----

This is more verbose, but, by building the `WebClient` with a `MockMvc` instance, we have
the full power of MockMvc at our fingertips.

TIP: For additional information on creating a `MockMvc` instance, see
<<spring-mvc-test-server-setup-options>>.

[[spring-mvc-test-server-htmlunit-webdriver]]
===== MockMvc and WebDriver

In the previous sections, we have seen how to use MockMvc in conjunction with the raw
HtmlUnit APIs. In this section, we use additional abstractions within the Selenium
https://docs.seleniumhq.org/projects/webdriver/[WebDriver] to make things even easier.

[[spring-mvc-test-server-htmlunit-webdriver-why]]
====== Why WebDriver and MockMvc?

We can already use HtmlUnit and MockMvc, so why would we want to use WebDriver? The
Selenium WebDriver provides a very elegant API that lets us easily organize our code. To
better show how it works, we explore an example in this section.

NOTE: Despite being a part of https://docs.seleniumhq.org/[Selenium], WebDriver does not
require a Selenium Server to run your tests.

Suppose we need to ensure that a message is created properly. The tests involve finding
the HTML form input elements, filling them out, and making various assertions.

This approach results in numerous separate tests because we want to test error conditions
as well. For example, we want to ensure that we get an error if we fill out only part of
the form. If we fill out the entire form, the newly created message should be displayed
afterwards.

If one of the fields were named "`summary`", we might have something that resembles the
following repeated in multiple places within our tests:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	HtmlTextInput summaryInput = currentPage.getHtmlElementById("summary");
	summaryInput.setValueAttribute(summary);
----
[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	val summaryInput = currentPage.getHtmlElementById("summary")
	summaryInput.setValueAttribute(summary)
----

So what happens if we change the `id` to `smmry`? Doing so would force us to update all
of our tests to incorporate this change. This violates the DRY principle, so we should
ideally extract this code into its own method, as follows:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	public HtmlPage createMessage(HtmlPage currentPage, String summary, String text) {
		setSummary(currentPage, summary);
		// ...
	}

	public void setSummary(HtmlPage currentPage, String summary) {
		HtmlTextInput summaryInput = currentPage.getHtmlElementById("summary");
		summaryInput.setValueAttribute(summary);
	}
----

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	fun createMessage(currentPage: HtmlPage, summary:String, text:String) :HtmlPage{
		setSummary(currentPage, summary);
		// ...
	}

	fun setSummary(currentPage:HtmlPage , summary: String) {
		val summaryInput = currentPage.getHtmlElementById("summary")
		summaryInput.setValueAttribute(summary)
	}
----

Doing so ensures that we do not have to update all of our tests if we change the UI.

We might even take this a step further and place this logic within an `Object` that
represents the `HtmlPage` we are currently on, as the following example shows:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	public class CreateMessagePage {

		final HtmlPage currentPage;

		final HtmlTextInput summaryInput;

		final HtmlSubmitInput submit;

		public CreateMessagePage(HtmlPage currentPage) {
			this.currentPage = currentPage;
			this.summaryInput = currentPage.getHtmlElementById("summary");
			this.submit = currentPage.getHtmlElementById("submit");
		}

		public <T> T createMessage(String summary, String text) throws Exception {
			setSummary(summary);

			HtmlPage result = submit.click();
			boolean error = CreateMessagePage.at(result);

			return (T) (error ? new CreateMessagePage(result) : new ViewMessagePage(result));
		}

		public void setSummary(String summary) throws Exception {
			summaryInput.setValueAttribute(summary);
		}

		public static boolean at(HtmlPage page) {
			return "Create Message".equals(page.getTitleText());
		}
	}
----
[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	class CreateMessagePage(private val currentPage: HtmlPage) {

		val summaryInput: HtmlTextInput = currentPage.getHtmlElementById("summary")

		val submit: HtmlSubmitInput = currentPage.getHtmlElementById("submit")

		fun <T> createMessage(summary: String, text: String): T {
			setSummary(summary)

			val result = submit.click()
			val error = at(result)

			return (if (error) CreateMessagePage(result) else ViewMessagePage(result)) as T
		}

		fun setSummary(summary: String) {
			summaryInput.setValueAttribute(summary)
		}

		fun at(page: HtmlPage): Boolean {
			return "Create Message" == page.getTitleText()
		}
	}
}
----

Formerly, this pattern was known as the
https://github.com/SeleniumHQ/selenium/wiki/PageObjects[Page Object Pattern]. While we
can certainly do this with HtmlUnit, WebDriver provides some tools that we explore in the
following sections to make this pattern much easier to implement.

[[spring-mvc-test-server-htmlunit-webdriver-setup]]
====== MockMvc and WebDriver Setup

To use Selenium WebDriver with the Spring MVC Test framework, make sure that your project
includes a test dependency on `org.seleniumhq.selenium:selenium-htmlunit-driver`.

We can easily create a Selenium WebDriver that integrates with MockMvc by using the
`MockMvcHtmlUnitDriverBuilder` as the following example shows:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	WebDriver driver;

	@BeforeEach
	void setup(WebApplicationContext context) {
		driver = MockMvcHtmlUnitDriverBuilder
				.webAppContextSetup(context)
				.build();
	}
----
[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	lateinit var driver: WebDriver

	@BeforeEach
	fun setup(context: WebApplicationContext) {
		driver = MockMvcHtmlUnitDriverBuilder
				.webAppContextSetup(context)
				.build()
	}
----

NOTE: This is a simple example of using `MockMvcHtmlUnitDriverBuilder`. For more advanced
usage, see <<spring-mvc-test-server-htmlunit-webdriver-advanced-builder>>.

The preceding example ensures that any URL that references `localhost` as the server is
directed to our `MockMvc` instance without the need for a real HTTP connection. Any other
URL is requested by using a network connection, as normal. This lets us easily test the
use of CDNs.

[[spring-mvc-test-server-htmlunit-webdriver-usage]]
====== MockMvc and WebDriver Usage

Now we can use WebDriver as we normally would but without the need to deploy our
application to a Servlet container. For example, we can request the view to create a
message with the following:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	CreateMessagePage page = CreateMessagePage.to(driver);
----

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	val page = CreateMessagePage.to(driver)
----

We can then fill out the form and submit it to create a message, as follows:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	ViewMessagePage viewMessagePage =
			page.createMessage(ViewMessagePage.class, expectedSummary, expectedText);
----

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	val viewMessagePage =
		page.createMessage(ViewMessagePage::class, expectedSummary, expectedText)
----

This improves on the design of our <<spring-mvc-test-server-htmlunit-mah-usage, HtmlUnit test>>
by leveraging the Page Object Pattern. As we mentioned in
<<spring-mvc-test-server-htmlunit-webdriver-why>>, we can use the Page Object Pattern
with HtmlUnit, but it is much easier with WebDriver. Consider the following
`CreateMessagePage` implementation:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	public class CreateMessagePage
			extends AbstractPage { // <1>

		// <2>
		private WebElement summary;
		private WebElement text;

		// <3>
		@FindBy(css = "input[type=submit]")
		private WebElement submit;

		public CreateMessagePage(WebDriver driver) {
			super(driver);
		}

		public <T> T createMessage(Class<T> resultPage, String summary, String details) {
			this.summary.sendKeys(summary);
			this.text.sendKeys(details);
			this.submit.click();
			return PageFactory.initElements(driver, resultPage);
		}

		public static CreateMessagePage to(WebDriver driver) {
			driver.get("http://localhost:9990/mail/messages/form");
			return PageFactory.initElements(driver, CreateMessagePage.class);
		}
	}
----
<1> `CreateMessagePage` extends the `AbstractPage`. We do not go over the details of
`AbstractPage`, but, in summary, it contains common functionality for all of our pages.
For example, if our application has a navigational bar, global error messages, and other
features, we can place this logic in a shared location.
<2> We have a member variable for each of the parts of the HTML page in which we are
interested. These are of type `WebElement`. WebDriver's
https://github.com/SeleniumHQ/selenium/wiki/PageFactory[`PageFactory`] lets us remove a
lot of code from the HtmlUnit version of `CreateMessagePage` by automatically resolving
each `WebElement`. The
https://seleniumhq.github.io/selenium/docs/api/java/org/openqa/selenium/support/PageFactory.html#initElements-org.openqa.selenium.WebDriver-java.lang.Class-[`PageFactory#initElements(WebDriver,Class<T>)`]
method automatically resolves each `WebElement` by using the field name and looking it up
by the `id` or `name` of the element within the HTML page.
<3> We can use the
https://github.com/SeleniumHQ/selenium/wiki/PageFactory#making-the-example-work-using-annotations[`@FindBy` annotation]
to override the default lookup behavior. Our example shows how to use the `@FindBy`
annotation to look up our submit button with a `css` selector (*input[type=submit]*).

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	class CreateMessagePage(private val driver: WebDriver) : AbstractPage(driver) { // <1>

		// <2>
		private lateinit var summary: WebElement
		private lateinit var text: WebElement

		// <3>
		@FindBy(css = "input[type=submit]")
		private lateinit var submit: WebElement

		fun <T> createMessage(resultPage: Class<T>, summary: String, details: String): T {
			this.summary.sendKeys(summary)
			text.sendKeys(details)
			submit.click()
			return PageFactory.initElements(driver, resultPage)
		}
		companion object {
			fun to(driver: WebDriver): CreateMessagePage {
				driver.get("http://localhost:9990/mail/messages/form")
				return PageFactory.initElements(driver, CreateMessagePage::class.java)
			}
		}
	}
----
<1> `CreateMessagePage` extends the `AbstractPage`. We do not go over the details of
`AbstractPage`, but, in summary, it contains common functionality for all of our pages.
For example, if our application has a navigational bar, global error messages, and other
features, we can place this logic in a shared location.
<2> We have a member variable for each of the parts of the HTML page in which we are
interested. These are of type `WebElement`. WebDriver's
https://github.com/SeleniumHQ/selenium/wiki/PageFactory[`PageFactory`] lets us remove a
lot of code from the HtmlUnit version of `CreateMessagePage` by automatically resolving
each `WebElement`. The
https://seleniumhq.github.io/selenium/docs/api/java/org/openqa/selenium/support/PageFactory.html#initElements-org.openqa.selenium.WebDriver-java.lang.Class-[`PageFactory#initElements(WebDriver,Class<T>)`]
method automatically resolves each `WebElement` by using the field name and looking it up
by the `id` or `name` of the element within the HTML page.
<3> We can use the
https://github.com/SeleniumHQ/selenium/wiki/PageFactory#making-the-example-work-using-annotations[`@FindBy` annotation]
to override the default lookup behavior. Our example shows how to use the `@FindBy`
annotation to look up our submit button with a `css` selector (*input[type=submit]*).


Finally, we can verify that a new message was created successfully. The following
assertions use the https://joel-costigliola.github.io/assertj/[AssertJ] assertion library:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	assertThat(viewMessagePage.getMessage()).isEqualTo(expectedMessage);
	assertThat(viewMessagePage.getSuccess()).isEqualTo("Successfully created a new message");
----
[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	assertThat(viewMessagePage.message.isEqualTo(expectedMessage)
	assertThat(viewMessagePage.success.isEqualTo("Successfully created a new message")
----

We can see that our `ViewMessagePage` lets us interact with our custom domain model. For
example, it exposes a method that returns a `Message` object:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	public Message getMessage() throws ParseException {
		Message message = new Message();
		message.setId(getId());
		message.setCreated(getCreated());
		message.setSummary(getSummary());
		message.setText(getText());
		return message;
	}
----
[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	fun getMessage() = Message(getId(), getCreated(), getSummary(), getText())
----

We can then use the rich domain objects in our assertions.

Lastly, we must not forget to close the `WebDriver` instance when the test is complete,
as follows:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	@AfterEach
	void destroy() {
		if (driver != null) {
			driver.close();
		}
	}
----

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	@AfterEach
	fun destroy() {
		if (driver != null) {
			driver.close()
		}
	}
----

For additional information on using WebDriver, see the Selenium
https://github.com/SeleniumHQ/selenium/wiki/Getting-Started[WebDriver documentation].

[[spring-mvc-test-server-htmlunit-webdriver-advanced-builder]]
====== Advanced `MockMvcHtmlUnitDriverBuilder`

In the examples so far, we have used `MockMvcHtmlUnitDriverBuilder` in the simplest way
possible, by building a `WebDriver` based on the `WebApplicationContext` loaded for us by
the Spring TestContext Framework. This approach is repeated here, as follows:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	WebDriver driver;

	@BeforeEach
	void setup(WebApplicationContext context) {
		driver = MockMvcHtmlUnitDriverBuilder
				.webAppContextSetup(context)
				.build();
	}
----

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	lateinit var driver: WebDriver

	@BeforeEach
	fun setup(context: WebApplicationContext) {
		driver = MockMvcHtmlUnitDriverBuilder
				.webAppContextSetup(context)
				.build()
	}
----

We can also specify additional configuration options, as follows:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	WebDriver driver;

	@BeforeEach
	void setup() {
		driver = MockMvcHtmlUnitDriverBuilder
				// demonstrates applying a MockMvcConfigurer (Spring Security)
				.webAppContextSetup(context, springSecurity())
				// for illustration only - defaults to ""
				.contextPath("")
				// By default MockMvc is used for localhost only;
				// the following will use MockMvc for example.com and example.org as well
				.useMockMvcForHosts("example.com","example.org")
				.build();
	}
----
[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	lateinit var driver: WebDriver

	@BeforeEach
	fun setup() {
		driver = MockMvcHtmlUnitDriverBuilder
				// demonstrates applying a MockMvcConfigurer (Spring Security)
				.webAppContextSetup(context, springSecurity())
				// for illustration only - defaults to ""
				.contextPath("")
				// By default MockMvc is used for localhost only;
				// the following will use MockMvc for example.com and example.org as well
				.useMockMvcForHosts("example.com","example.org")
				.build()
	}
----

As an alternative, we can perform the exact same setup by configuring the `MockMvc`
instance separately and supplying it to the `MockMvcHtmlUnitDriverBuilder`, as follows:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	MockMvc mockMvc = MockMvcBuilders
			.webAppContextSetup(context)
			.apply(springSecurity())
			.build();

	driver = MockMvcHtmlUnitDriverBuilder
			.mockMvcSetup(mockMvc)
			// for illustration only - defaults to ""
			.contextPath("")
			// By default MockMvc is used for localhost only;
			// the following will use MockMvc for example.com and example.org as well
			.useMockMvcForHosts("example.com","example.org")
			.build();
----

[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	// Not possible in Kotlin until https://youtrack.jetbrains.com/issue/KT-22208 is fixed
----

This is more verbose, but, by building the `WebDriver` with a `MockMvc` instance, we have
the full power of MockMvc at our fingertips.

TIP: For additional information on creating a `MockMvc` instance, see
<<spring-mvc-test-server-setup-options>>.

[[spring-mvc-test-server-htmlunit-geb]]
===== MockMvc and Geb

In the previous section, we saw how to use MockMvc with WebDriver. In this section, we
use http://www.gebish.org/[Geb] to make our tests even Groovy-er.

[[spring-mvc-test-server-htmlunit-geb-why]]
====== Why Geb and MockMvc?

Geb is backed by WebDriver, so it offers many of the
<<spring-mvc-test-server-htmlunit-webdriver-why, same benefits>> that we get from
WebDriver. However, Geb makes things even easier by taking care of some of the
boilerplate code for us.

[[spring-mvc-test-server-htmlunit-geb-setup]]
====== MockMvc and Geb Setup

We can easily initialize a Geb `Browser` with a Selenium WebDriver that uses MockMvc, as
follows:

[source,groovy]
----
def setup() {
	browser.driver = MockMvcHtmlUnitDriverBuilder
		.webAppContextSetup(context)
		.build()
}
----

NOTE: This is a simple example of using `MockMvcHtmlUnitDriverBuilder`. For more advanced
usage, see <<spring-mvc-test-server-htmlunit-webdriver-advanced-builder>>.

This ensures that any URL referencing `localhost` as the server is directed to our
`MockMvc` instance without the need for a real HTTP connection. Any other URL is
requested by using a network connection as normal. This lets us easily test the use of
CDNs.

[[spring-mvc-test-server-htmlunit-geb-usage]]
====== MockMvc and Geb Usage

Now we can use Geb as we normally would but without the need to deploy our application to
a Servlet container. For example, we can request the view to create a message with the
following:

[source,groovy]
----
to CreateMessagePage
----

We can then fill out the form and submit it to create a message, as follows:

[source,groovy]
----
when:
form.summary = expectedSummary
form.text = expectedMessage
submit.click(ViewMessagePage)
----

Any unrecognized method calls or property accesses or references that are not found are
forwarded to the current page object. This removes a lot of the boilerplate code we
needed when using WebDriver directly.

As with direct WebDriver usage, this improves on the design of our
<<spring-mvc-test-server-htmlunit-mah-usage, HtmlUnit test>> by using the Page Object
Pattern. As mentioned previously, we can use the Page Object Pattern with HtmlUnit and
WebDriver, but it is even easier with Geb. Consider our new Groovy-based
`CreateMessagePage` implementation:

[source,groovy]
----
class CreateMessagePage extends Page {
	static url = 'messages/form'
	static at = { assert title == 'Messages : Create'; true }
	static content =  {
		submit { $('input[type=submit]') }
		form { $('form') }
		errors(required:false) { $('label.error, .alert-error')?.text() }
	}
}
----

Our `CreateMessagePage` extends `Page`. We do not go over the details of `Page`, but, in
summary, it contains common functionality for all of our pages. We define a URL in which
this page can be found. This lets us navigate to the page, as follows:

[source,groovy]
----
to CreateMessagePage
----

We also have an `at` closure that determines if we are at the specified page. It should
return `true` if we are on the correct page. This is why we can assert that we are on the
correct page, as follows:

[source,groovy]
----
then:
at CreateMessagePage
errors.contains('This field is required.')
----

NOTE: We use an assertion in the closure so that we can determine where things went wrong
if we were at the wrong page.

Next, we create a `content` closure that specifies all the areas of interest within the
page. We can use a
http://www.gebish.org/manual/current/#the-jquery-ish-navigator-api[jQuery-ish Navigator
API] to select the content in which we are interested.

Finally, we can verify that a new message was created successfully, as follows:

[source,groovy]
----
then:
at ViewMessagePage
success == 'Successfully created a new message'
id
date
summary == expectedSummary
message == expectedMessage
----

For further details on how to get the most out of Geb, see
http://www.gebish.org/manual/current/[The Book of Geb] user's manual.


[[spring-mvc-test-client]]
==== Client-Side REST Tests

You can use client-side tests to test code that internally uses the `RestTemplate`. The
idea is to declare expected requests and to provide "`stub`" responses so that you can
focus on testing the code in isolation (that is, without running a server). The following
example shows how to do so:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	RestTemplate restTemplate = new RestTemplate();

	MockRestServiceServer mockServer = MockRestServiceServer.bindTo(restTemplate).build();
	mockServer.expect(requestTo("/greeting")).andRespond(withSuccess());

	// Test code that uses the above RestTemplate ...

	mockServer.verify();
----
[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	val restTemplate = RestTemplate()

	val mockServer = MockRestServiceServer.bindTo(restTemplate).build()
	mockServer.expect(requestTo("/greeting")).andRespond(withSuccess())

	// Test code that uses the above RestTemplate ...

	mockServer.verify()
----

In the preceding example, `MockRestServiceServer` (the central class for client-side REST
tests) configures the `RestTemplate` with a custom `ClientHttpRequestFactory` that
asserts actual requests against expectations and returns "`stub`" responses. In this
case, we expect a request to `/greeting` and want to return a 200 response with
`text/plain` content. We can define additional expected requests and stub responses as
needed. When we define expected requests and stub responses, the `RestTemplate` can be
used in client-side code as usual. At the end of testing, `mockServer.verify()` can be
used to verify that all expectations have been satisfied.

By default, requests are expected in the order in which expectations were declared. You
can set the `ignoreExpectOrder` option when building the server, in which case all
expectations are checked (in order) to find a match for a given request. That means
requests are allowed to come in any order. The following example uses `ignoreExpectOrder`:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	server = MockRestServiceServer.bindTo(restTemplate).ignoreExpectOrder(true).build();
----
[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	server = MockRestServiceServer.bindTo(restTemplate).ignoreExpectOrder(true).build()
----

Even with unordered requests by default, each request is allowed to execute once only.
The `expect` method provides an overloaded variant that accepts an `ExpectedCount`
argument that specifies a count range (for example, `once`, `manyTimes`, `max`, `min`,
`between`, and so on). The following example uses `times`:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	RestTemplate restTemplate = new RestTemplate();

	MockRestServiceServer mockServer = MockRestServiceServer.bindTo(restTemplate).build();
	mockServer.expect(times(2), requestTo("/something")).andRespond(withSuccess());
	mockServer.expect(times(3), requestTo("/somewhere")).andRespond(withSuccess());

	// ...

	mockServer.verify();
----
[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	val restTemplate = RestTemplate()

	val mockServer = MockRestServiceServer.bindTo(restTemplate).build()
	mockServer.expect(times(2), requestTo("/something")).andRespond(withSuccess())
	mockServer.expect(times(3), requestTo("/somewhere")).andRespond(withSuccess())

	// ...

	mockServer.verify()
----

Note that, when `ignoreExpectOrder` is not set (the default), and, therefore, requests
are expected in order of declaration, then that order applies only to the first of any
expected request. For example if "/something" is expected two times followed by
"/somewhere" three times, then there should be a request to "/something" before there is
a request to "/somewhere", but, aside from that subsequent "/something" and "/somewhere",
requests can come at any time.

As an alternative to all of the above, the client-side test support also provides a
`ClientHttpRequestFactory` implementation that you can configure into a `RestTemplate` to
bind it to a `MockMvc` instance. That allows processing requests using actual server-side
logic but without running a server. The following example shows how to do so:

[source,java,indent=0,subs="verbatim,quotes",role="primary"]
.Java
----
	MockMvc mockMvc = MockMvcBuilders.webAppContextSetup(this.wac).build();
	this.restTemplate = new RestTemplate(new MockMvcClientHttpRequestFactory(mockMvc));

	// Test code that uses the above RestTemplate ...
----
[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
.Kotlin
----
	val mockMvc = MockMvcBuilders.webAppContextSetup(this.wac).build()
	restTemplate = RestTemplate(MockMvcClientHttpRequestFactory(mockMvc))

	// Test code that uses the above RestTemplate ...
----

[[spring-mvc-test-client-static-imports]]
===== Static Imports

As with server-side tests, the fluent API for client-side tests requires a few static
imports. Those are easy to find by searching for `MockRest*`. Eclipse users should add
`MockRestRequestMatchers.{asterisk}` and `MockRestResponseCreators.{asterisk}` as
"`favorite static members`" in the Eclipse preferences under Java -> Editor -> Content
Assist -> Favorites. That allows using content assist after typing the first character of
the static method name. Other IDEs (such IntelliJ) may not require any additional
configuration. Check for the support for code completion on static members.

[[spring-mvc-test-client-resources]]
===== Further Examples of Client-side REST Tests

Spring MVC Test's own tests include
https://github.com/spring-projects/spring-framework/tree/master/spring-test/src/test/java/org/springframework/test/web/client/samples[example
tests] of client-side REST tests.

include::testing-webtestclient.adoc[leveloffset=+2]



[[testing-resources]]
== Further Resources
See the following resources for more information about testing:

* https://www.junit.org/[JUnit]: "`A programmer-friendly testing framework for Java`".
  Used by the Spring Framework in its test suite and supported in the
  <<testcontext-framework, Spring TestContext Framework>>.
* https://testng.org/[TestNG]: A testing framework inspired by JUnit with added support
  for test groups, data-driven testing, distributed testing, and other features. Supported
  in the <<testcontext-framework, Spring TestContext Framework>>
* https://joel-costigliola.github.io/assertj/[AssertJ]: "`Fluent assertions for Java`",
  including support for Java 8 lambdas, streams, and other features.
* https://en.wikipedia.org/wiki/Mock_Object[Mock Objects]: Article in Wikipedia.
* http://www.mockobjects.com/[MockObjects.com]: Web site dedicated to mock objects, a
  technique for improving the design of code within test-driven development.
* https://mockito.github.io[Mockito]: Java mock library based on the
  http://xunitpatterns.com/Test%20Spy.html[Test Spy] pattern. Used by the Spring Framework
  in its test suite.
* https://easymock.org/[EasyMock]: Java library "`that provides Mock Objects for
  interfaces (and objects through the class extension) by generating them on the fly using
  Java's proxy mechanism.`"
* https://jmock.org/[JMock]: Library that supports test-driven development of Java code
  with mock objects.
* https://www.dbunit.org/[DbUnit]: JUnit extension (also usable with Ant and Maven) that
  is targeted at database-driven projects and, among other things, puts your database into
  a known state between test runs.
* https://sourceforge.net/projects/grinder/[The Grinder]: Java load testing framework.
* https://github.com/Ninja-Squad/springmockk[SpringMockK]: Support for Spring Boot
  integration tests written in Kotlin using https://mockk.io/[MockK] instead of Mockito.