Add codegen-template-test module with custom template support

.gitignore

@@ -11,6 +11,7 @@
 /.claude/
 /data/
 /.apt_generated/
+.kotlin/
 
 /src/main/java/codegen
 /src/main/kotlin/codegen

CLAUDE.md

@@ -23,6 +23,7 @@ Doma CodeGen Plugin is a Gradle plugin that generates Java, Kotlin, and SQL file
 ./gradlew :codegen:test
 ./gradlew :codegen-h2-test:test
 ./gradlew :codegen-tc-test:test
+./gradlew :codegen-template-test:test
 ```
 
 ## Code Quality
@@ -42,7 +43,7 @@ This is a Gradle composite build with the following structure:
 
 - **Root project** (`doma-codegen-plugin`): Contains build configuration and release management
   - Uses `pluginManagement` with `includeBuild("codegen")` to include the plugin project
-  - Includes test modules: `codegen-h2-test` and `codegen-tc-test`
+  - Includes test modules: `codegen-h2-test`, `codegen-tc-test`, and `codegen-template-test`
 
 - **codegen**: Main plugin implementation (included build)
   - Plugin entry point: `CodeGenPlugin.java`
@@ -62,6 +63,12 @@ This is a Gradle composite build with the following structure:
   - Supports both Java and Kotlin code generation
   - Two configurations: `java` and `kotlin`
 
+- **codegen-template-test**: Custom template demonstration module
+  - Tests code generation with custom FreeMarker templates
+  - Uses H2 in-memory database with custom template directory
+  - Single configuration: `customTemplate`
+  - Demonstrates how to override default templates with custom ones
+
 ### Key Components
 
 1. **Code Generators**: Transform database metadata into Java/Kotlin code using FreeMarker templates
@@ -75,6 +82,7 @@ This is a Gradle composite build with the following structure:
 
 4. **Template System**: FreeMarker templates in `/codegen/src/main/resources/`
    - Customizable via `templateDir` configuration
+   - See `codegen-template-test` module for custom template examples
 
 ### Development Notes
 
@@ -94,6 +102,10 @@ domaCodeGen {
         url = "jdbc:h2:mem:example"
         user = "sa"
         password = ""
+
+        // Optional: Use custom templates
+        templateDir = file("src/main/resources/custom-templates")
+
         entity {
             packageName = "com.example.entity"
         }
@@ -104,6 +116,14 @@ domaCodeGen {
 }
 ```
 
+### Custom Templates
+
+The plugin supports custom FreeMarker templates to override default code generation:
+- Place custom templates in a directory (e.g., `src/main/resources/custom-templates/`)
+- Configure `templateDir` property in `domaCodeGen` configuration
+- Template files: `entity.ftl`, `dao.ftl`, `selectById.sql.ftl`, `lib.ftl`
+- See `codegen-template-test` module for a complete example
+
 ### Important Notes
 
 - The plugin is published to Gradle Plugin Portal (not Maven Central)

codegen-template-test/.gitignore

@@ -0,0 +1,18 @@
+/.classpath
+/.gradle/
+/.project
+/.settings/
+/bin/
+/build/
+/target/
+/.metadata
+/.idea/
+.factorypath
+/.claude/
+/data/
+/.apt_generated/
+
+/src/main/java/com/example/template/entity/
+/src/main/java/com/example/template/dao/
+/src/main/resources/META-INF/com/example/template/dao/
+/src/test/java/com/example/template/dao/

codegen-template-test/README.md

@@ -0,0 +1,81 @@
+# Template Test Module
+
+This module demonstrates how to use custom FreeMarker templates with the Doma CodeGen Plugin.
+
+## Overview
+
+The `codegen-template-test` module shows how to:
+- Configure custom template directories
+- Create custom FreeMarker templates for entities, DAOs, and SQL files
+- Override default code generation behavior
+
+## Configuration
+
+The module uses custom templates located in `src/main/resources/custom-templates/`:
+
+```kotlin
+domaCodeGen {
+    register("customTemplate") {
+        // ... database configuration ...
+
+        // Use custom templates
+        templateDir = file("src/main/resources/custom-templates")
+    }
+}
+```
+
+## Custom Templates
+
+### Entity Template (`entity.ftl`)
+The custom entity template adds:
+- Serializable interface implementation (`implements java.io.Serializable`)
+- Custom helper method `getEntityName()` that returns the entity class name
+- Custom copyright header with generation timestamp
+- Custom author information via lib.ftl
+
+### DAO Template (`dao.ftl`)
+The custom DAO template adds:
+- `@MultiInsert` annotation for batch insert operations
+- Custom method `insertMulti(List<Entity>)` for bulk inserts
+- Custom copyright header with generation timestamp
+- Custom author information via lib.ftl
+
+### SQL Template (`selectById.sql.ftl`)
+The custom SQL template:
+- Explicitly lists all columns instead of using SELECT *
+- Includes formatted SQL with proper indentation
+
+### Shared Template (`lib.ftl`)
+Contains shared utilities:
+- Custom copyright header with project name and generation timestamp
+- Author information ("Custom Template Generator")
+
+## Testing
+
+Run tests with:
+```bash
+./gradlew :codegen-template-test:test
+```
+
+The tests verify:
+- Code generation completes successfully
+- Custom headers are present in generated files ("This file was generated by Doma-CodeGen with custom templates")
+- Entities implement Serializable interface
+- Entities have custom `getEntityName()` method
+- DAOs have custom `insertMulti(List<Entity>)` method
+- All expected files are created
+
+## Database Schema
+
+The module uses an H2 in-memory database with three tables:
+- `department` - Department master table with various column types
+- `employee` - Employee table with foreign key and version column
+- `product` - Product catalog table demonstrating different data types
+
+## Notes
+
+- The generated code includes custom headers showing it was created with custom templates
+- Templates are placed directly in `src/main/resources/custom-templates/` (entity.ftl, dao.ftl, etc.)
+- Templates can access all properties from EntityDesc and DaoDesc classes
+- The lib.ftl file contains shared template utilities like copyright headers and author information
+- Custom templates override the default Doma templates when `templateDir` is configured

codegen-template-test/build.gradle.kts

@@ -0,0 +1,76 @@
+plugins {
+    java
+    alias(libs.plugins.doma.compile)
+    id("org.domaframework.doma.codegen")
+}
+
+java {
+    toolchain.languageVersion.set(JavaLanguageVersion.of(17))
+}
+
+repositories {
+    mavenLocal()
+    mavenCentral()
+}
+
+dependencies {
+    implementation(libs.doma.core)
+    annotationProcessor(libs.doma.processor)
+
+    testImplementation(platform(libs.junit.bom))
+    testImplementation(libs.junit.jupiter.api)
+    testRuntimeOnly(libs.junit.jupiter.engine)
+    testRuntimeOnly(libs.junit.platform.launcher)
+    testImplementation(libs.h2)
+
+    domaCodeGen(libs.h2)
+}
+
+val initScript = file("init_h2.sql")
+
+domaCodeGen {
+    register("customTemplate") {
+        url = "jdbc:h2:mem:template_test;INIT=RUNSCRIPT FROM 'file:${initScript.absolutePath}'"
+        user = "sa"
+        password = ""
+        schemaName = "PUBLIC"
+
+        // Use custom templates
+        templateDir = file("src/main/resources/custom-templates")
+
+        // Generate both entity and dao
+        entity {
+            packageName = "com.example.template.entity"
+        }
+        dao {
+            packageName = "com.example.template.dao"
+        }
+    }
+}
+
+tasks {
+    compileJava {
+        dependsOn("domaCodeGenCustomTemplateAll")
+    }
+
+    compileTestJava {
+        dependsOn(compileJava)
+    }
+
+    test {
+        useJUnitPlatform()
+    }
+
+    val deleteSrc = register("deleteSrc") {
+        doLast {
+            delete("src/main/java/com/example/template/entity")
+            delete("src/main/java/com/example/template/dao")
+            delete("src/main/resources/META-INF/com/example/template/dao")
+            delete("src/test/java/com/example/template/dao")
+        }
+    }
+
+    clean {
+        dependsOn(deleteSrc)
+    }
+}

codegen-template-test/init_h2.sql

@@ -0,0 +1,53 @@
+-- Initialization script for template test database
+-- This creates sample tables to test custom template generation
+
+-- Department table with various column types
+CREATE TABLE department (
+    dept_id INTEGER NOT NULL PRIMARY KEY,
+    dept_name VARCHAR(100) NOT NULL,
+    location VARCHAR(200),
+    created_date DATE DEFAULT CURRENT_DATE,
+    active BOOLEAN DEFAULT TRUE,
+    description CLOB,
+    budget DECIMAL(15,2)
+);
+
+-- Employee table with relationships and versioning
+CREATE TABLE employee (
+    emp_id INTEGER NOT NULL GENERATED BY DEFAULT AS IDENTITY PRIMARY KEY,
+    emp_name VARCHAR(100) NOT NULL,
+    email VARCHAR(255) UNIQUE,
+    dept_id INTEGER,
+    hire_date DATE NOT NULL,
+    salary DECIMAL(10,2),
+    version INTEGER NOT NULL DEFAULT 1,
+    notes TEXT,
+    CONSTRAINT fk_dept FOREIGN KEY (dept_id) REFERENCES department(dept_id)
+);
+
+-- Product table to test different data types
+CREATE TABLE product (
+    product_code VARCHAR(20) NOT NULL PRIMARY KEY,
+    product_name VARCHAR(200) NOT NULL,
+    category VARCHAR(50),
+    price DECIMAL(10,2) NOT NULL,
+    stock_quantity INTEGER DEFAULT 0,
+    manufacturing_date DATE,
+    expiry_date DATE,
+    is_available BOOLEAN DEFAULT TRUE,
+    last_updated TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
+    product_info CLOB,
+    tags VARCHAR(500)
+);
+
+-- Add table comments for testing
+COMMENT ON TABLE department IS 'Department master table';
+COMMENT ON TABLE employee IS 'Employee information table';
+COMMENT ON TABLE product IS 'Product catalog table';
+
+-- Add column comments
+COMMENT ON COLUMN department.dept_id IS 'Department unique identifier';
+COMMENT ON COLUMN department.dept_name IS 'Department name';
+COMMENT ON COLUMN employee.emp_id IS 'Employee ID (auto-generated)';
+COMMENT ON COLUMN employee.version IS 'Version for optimistic locking';
+COMMENT ON COLUMN product.product_code IS 'Product SKU code';

codegen-template-test/src/main/resources/custom-templates/dao.ftl

@@ -0,0 +1,73 @@
+<#-- Custom dao.ftl -->
+<#import "/lib.ftl" as lib>
+<#if lib.copyright??>
+${lib.copyright}
+</#if>
+<#if packageName??>
+package ${packageName};
+</#if>
+
+<#list importNames as importName>
+import ${importName};
+</#list>
+import org.seasar.doma.MultiInsert;
+
+/**
+<#if lib.author??>
+ * @author ${lib.author}
+</#if>
+ */
+@Dao<#if configClassSimpleName??>(config = ${configClassSimpleName}.class)</#if>
+public interface ${simpleName} {
+
+<#if entityDesc.idEntityPropertyDescs?size gt 0>
+    /**
+<#list entityDesc.idEntityPropertyDescs as property>
+     * @param ${property.name}
+</#list>
+     * @return the <#if entityDesc.entityPrefix??>${entityDesc.entityPrefix}</#if>${entityDesc.simpleName}<#if entityDesc.entitySuffix??>${entityDesc.entitySuffix}</#if> entity
+     */
+    @Select
+    <#if entityDesc.entityPrefix??>${entityDesc.entityPrefix}</#if>${entityDesc.simpleName}<#if entityDesc.entitySuffix??>${entityDesc.entitySuffix}</#if> selectById(<#list entityDesc.idEntityPropertyDescs as property>${property.propertyClassSimpleName} ${property.name}<#if property_has_next>, </#if></#list>);
+
+</#if>
+<#if entityDesc.idEntityPropertyDescs?size gt 0 && entityDesc.versionEntityPropertyDesc??>
+    /**
+<#list entityDesc.idEntityPropertyDescs as property>
+     * @param ${property.name}
+</#list>
+     * @param ${entityDesc.versionEntityPropertyDesc.name}
+     * @return the <#if entityDesc.entityPrefix??>${entityDesc.entityPrefix}</#if>${entityDesc.simpleName}<#if entityDesc.entitySuffix??>${entityDesc.entitySuffix}</#if> entity
+     */
+    @Select(ensureResult = true)
+    <#if entityDesc.entityPrefix??>${entityDesc.entityPrefix}</#if>${entityDesc.simpleName}<#if entityDesc.entitySuffix??>${entityDesc.entitySuffix}</#if> selectByIdAndVersion(<#list entityDesc.idEntityPropertyDescs as property>${property.propertyClassSimpleName} ${property.name}, </#list>${entityDesc.versionEntityPropertyDesc.propertyClassSimpleName} ${entityDesc.versionEntityPropertyDesc.name});
+
+</#if>
+    /**
+     * @param entity
+     * @return affected rows
+     */
+    @Insert
+    int insert(<#if entityDesc.entityPrefix??>${entityDesc.entityPrefix}</#if>${entityDesc.simpleName}<#if entityDesc.entitySuffix??>${entityDesc.entitySuffix}</#if> entity);
+
+    /**
+     * @param entities
+     * @return affected rows
+     */
+    @MultiInsert
+    int insertMulti(java.util.List<<#if entityDesc.entityPrefix??>${entityDesc.entityPrefix}</#if>${entityDesc.simpleName}<#if entityDesc.entitySuffix??>${entityDesc.entitySuffix}</#if>> entities);
+
+    /**
+     * @param entity
+     * @return affected rows
+     */
+    @Update
+    int update(<#if entityDesc.entityPrefix??>${entityDesc.entityPrefix}</#if>${entityDesc.simpleName}<#if entityDesc.entitySuffix??>${entityDesc.entitySuffix}</#if> entity);
+
+    /**
+     * @param entity
+     * @return affected rows
+     */
+    @Delete
+    int delete(<#if entityDesc.entityPrefix??>${entityDesc.entityPrefix}</#if>${entityDesc.simpleName}<#if entityDesc.entitySuffix??>${entityDesc.entitySuffix}</#if> entity);
+}