[KTLN-889] Kotlin DI Frameworks (#1105)

* Undo wrong file

* code changes

* Restoring deleted file

* code refactoring

* code refactor

---------

Co-authored-by: nappy29 <[email protected]>

Author: naoussi

core-kotlin-modules/core-kotlin-design-patterns-1/pom.xml

@@ -0,0 +1,56 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+    <parent>
+        <groupId>com.baeldung</groupId>
+        <artifactId>core-kotlin-modules</artifactId>
+        <version>1.0.0-SNAPSHOT</version>
+    </parent>
+
+    <artifactId>core-kotlin-design-patterns-1</artifactId>
+
+    <properties>
+        <koin-core-jvm.version>3.5.6</koin-core-jvm.version>
+        <koin-core.version>3.4.0</koin-core.version>
+        <koin-test.version>3.4.0</koin-test.version>
+        <kodein-di-jvm.version>7.11.0</kodein-di-jvm.version>
+        <guice.version>5.0.1</guice.version>
+    </properties>
+
+    <dependencies>
+        <dependency>
+            <groupId>io.insert-koin</groupId>
+            <artifactId>koin-core-jvm</artifactId>
+            <version>${koin-core-jvm.version}</version>
+        </dependency>
+
+        <dependency>
+            <groupId>io.insert-koin</groupId>
+            <artifactId>koin-core</artifactId>
+            <version>${koin-core.version}</version>
+        </dependency>
+
+        <dependency>
+            <groupId>io.insert-koin</groupId>
+            <artifactId>koin-test</artifactId>
+            <version>${koin-test.version}</version>
+            <scope>test</scope>
+        </dependency>
+
+        <dependency>
+            <groupId>org.kodein.di</groupId>
+            <artifactId>kodein-di-jvm</artifactId>
+            <version>${kodein-di-jvm.version}</version>
+        </dependency>
+
+        <dependency>
+            <groupId>com.google.inject</groupId>
+            <artifactId>guice</artifactId>
+            <version>${guice.version}</version>
+        </dependency>
+    </dependencies>
+
+
+</project>

core-kotlin-modules/core-kotlin-design-patterns-1/src/test/kotlin/com/baeldung/di/UserService.kt

@@ -0,0 +1,5 @@
+package com.baeldung.di
+
+interface UserService {
+    fun getUser(): String
+}

core-kotlin-modules/core-kotlin-design-patterns-1/src/test/kotlin/com/baeldung/di/UserServiceImpl.kt

@@ -0,0 +1,7 @@
+package com.baeldung.di
+
+import com.baeldung.di.UserService
+
+class UserServiceImpl : UserService {
+    override fun getUser(): String = "John Doe"
+}

core-kotlin-modules/core-kotlin-design-patterns-1/src/test/kotlin/com/baeldung/di/guice/GuiceUnitTest.kt

@@ -0,0 +1,21 @@
+package com.baeldung.di.guice
+
+import com.baeldung.di.UserService
+import com.google.inject.Guice
+import com.google.inject.Inject
+import com.google.inject.Injector
+import org.junit.jupiter.api.Assertions.assertEquals
+import org.junit.jupiter.api.Test
+
+class GuiceUnitTest {
+    @Inject
+    private lateinit var userService: UserService
+
+    @Test
+    fun `obtain dependency using guice`() {
+        val injector: Injector = Guice.createInjector(UserModule())
+        injector.injectMembers(this)
+
+        assertEquals("John Doe", userService.getUser())
+    }
+}

core-kotlin-modules/core-kotlin-design-patterns-1/src/test/kotlin/com/baeldung/di/guice/UserModule.kt

@@ -0,0 +1,11 @@
+package com.baeldung.di.guice
+
+import com.baeldung.di.UserService
+import com.baeldung.di.UserServiceImpl
+import com.google.inject.AbstractModule
+
+class UserModule : AbstractModule() {
+    override fun configure() {
+        bind(UserService::class.java).to(UserServiceImpl::class.java)
+    }
+}

core-kotlin-modules/core-kotlin-design-patterns-1/src/test/kotlin/com/baeldung/di/kodein/KodeinUnitTest.kt

@@ -0,0 +1,23 @@
+package com.baeldung.di.kodein
+
+import com.baeldung.di.UserService
+import com.baeldung.di.UserServiceImpl
+import org.junit.jupiter.api.Test
+import org.kodein.di.DI
+import org.kodein.di.bind
+import org.kodein.di.instance
+import org.kodein.di.singleton
+import kotlin.test.assertEquals
+
+val kodein = DI {
+    bind<UserService>() with singleton { UserServiceImpl() }
+}
+
+class KodeinUnitTest {
+    private val userService: UserService by kodein.instance()
+
+    @Test
+    fun `obtain dependency using kodein`(){
+        assertEquals("John Doe", userService.getUser())
+    }
+}

core-kotlin-modules/core-kotlin-design-patterns-1/src/test/kotlin/com/baeldung/di/kodein/UserComponent.kt

@@ -0,0 +1,6 @@
+package com.baeldung.di.kodein
+
+
+interface UserComponent {
+    fun inject(app: KodeinUnitTest)
+}

core-kotlin-modules/core-kotlin-design-patterns-1/src/test/kotlin/com/baeldung/di/koin/DependencyInjectionUnitTest.kt

@@ -0,0 +1,26 @@
+package com.baeldung.di.koin
+
+import com.baeldung.di.UserService
+import com.baeldung.di.UserServiceImpl
+import org.junit.jupiter.api.Assertions.assertEquals
+import org.junit.jupiter.api.Test
+import org.koin.core.context.startKoin
+import org.koin.dsl.module
+import org.koin.core.component.KoinComponent
+import org.koin.core.component.inject
+import org.koin.core.module.Module
+
+
+class DependencyInjectionUnitTest: KoinComponent {
+
+    val appModule: Module = module { single<UserService> { UserServiceImpl() } }
+    private val service: UserService by inject()
+
+    @Test
+    fun `DI demonstration with Koin`() {
+        startKoin {
+            modules(appModule)
+        }
+        assertEquals("John Doe", service.getUser())
+    }
+}

core-kotlin-modules/core-kotlin-design-patterns/pom.xml

@@ -13,4 +13,5 @@
         <version>1.0.0-SNAPSHOT</version>
     </parent>
 
+
 </project>

core-kotlin-modules/pom.xml

@@ -75,6 +75,7 @@
         <module>core-kotlin-operators</module>
         <module>core-kotlin-concurrency-3</module>
         <module>core-kotlin-concurrency-4</module>
+        <module>core-kotlin-design-patterns-1</module>
     </modules>
 
 </project>