example-codegen-plugin

example-codegen-plugin

A sample project demonstrating code generation using the Doma Codegen Plugin.

Overview

This project demonstrates how to use the Doma Codegen Plugin to automatically generate entity classes and DAO classes from database schemas.

It supports both MySQL and PostgreSQL databases and uses Testcontainers to automatically start databases during code generation.

Project Structure

example-codegen-plugin/
├── build.gradle.kts           # Build configuration file
├── src/
│   ├── main/
│   │   ├── java/
│   │   │   └── example/
│   │   │       └── generated/  # Auto-generated code
│   │   │           ├── mysql/
│   │   │           │   ├── dao/      # MySQL DAO classes
│   │   │           │   └── entity/   # MySQL entity classes
│   │   │           └── postgresql/
│   │   │               ├── dao/      # PostgreSQL DAO classes
│   │   │               └── entity/   # PostgreSQL entity classes
│   │   └── resources/
│   │       ├── META-INF/       # Auto-generated SQL files
│   │       ├── init_mysql.sql      # MySQL initialization script
│   │       └── init_postgresql.sql # PostgreSQL initialization script
│   └── test/
│       └── java/
│           └── example/
│               └── generated/  # Auto-generated test code

Generated Tables

Code is generated from the following four tables:

• DEPARTMENT - Department information
• ADDRESS - Address information
• EMPLOYEE - Employee information (with foreign key constraints to DEPARTMENT and ADDRESS)
• COMP_KEY_ADDRESS - Address information with composite primary key

Usage

Code Generation

Generate code for MySQL

./gradlew domaCodeGenMysqlAll

Generate code for PostgreSQL

./gradlew domaCodeGenPostgresqlAll

Clean up generated code

./gradlew clean

Run tests

./gradlew test

Configuration

The following configurations are set in build.gradle.kts:

MySQL Configuration

• Uses Testcontainers MySQL
• Initialization script: src/main/resources/init_mysql.sql
• Generated packages:
  • Entities: example.generated.mysql.entity
  • DAOs: example.generated.mysql.dao

PostgreSQL Configuration

• Uses Testcontainers PostgreSQL
• Initialization script: src/main/resources/init_postgresql.sql
• Generated packages:
  • Entities: example.generated.postgresql.entity
  • DAOs: example.generated.postgresql.dao

Requirements

• Java 17 or higher
• Docker (required for running Testcontainers)

References

• Doma Official Documentation
• Doma Codegen Plugin
• Testcontainers