Java Service Template

This is a template for creating new Java services. It is built using Java 17 and Spring Boot, with added support for:

• Multi-tenant MySQL databases
• Redis for caching
• Flyway for database migration
• kafka Integration as producer

Maintainers

Manager	Developer
Manager	Dev Names

Built With

• Java 17
• Spring Boot 3.1.4
• Maven

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Clean Architecture Overview

Below is the Clean Architecture Diagram showcasing Dependency Injection and Layered Responsibility:

• Controller Layer: Handles HTTP requests.
• Use Case Layer: Implements business logic.
• Domain Layer: Contains core domain models.
• Repository Layer: Interface to data persistence.
• Database Layer: Stores application data.

Dependency Injection is applied so that higher layers only depend on abstractions, not concrete implementations.

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Folder Structure

project-root/
├── src/main/java/com/olx/boilerplate/
│   ├── controller/    # Handles HTTP requests
│   ├── usercase/      # Business logic (Use Cases)
│   ├── domain/        # Core business models
│   ├── repository/    # Data access layer
│   ├── config/        # Configuration files
│   ├── infrastructure/ # External system integrations
│
├── src/test/java/com/olx/boilerplate/
│   ├── unit/          # Unit tests (mock dependencies)
│   ├── integration/   # Integration tests (end-to-end flows)
│
├── docker-compose-local.yml  # Local environment setup
├── migrate.sh                # DB migration script
├── README.md                 # Project documentation

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Local Setup

1. Start Docker.
2. Clone the repository and start the required containers:

   git clone {project-repo}
   cd {project-path}
   docker-compose -f docker-compose-local.yml up -d

3. Run Flyway migrations to initialize the database:

   ./migrate.sh

4. Start the Spring Boot Application with the local profile:

   mvn spring-boot:run -Dspring.profiles.active=local

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Features & Plugins

1. SpotBugs (Static code analysis)
2. Maven Formatter (Ensure code consistency)

   mvn formatter:format

3. Dependency Check (Find vulnerable dependencies)
4. Jarvis (Integration Tests)

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Integration Testing (IT) - Example .feature Files

Create User API Test

Scenario: Create a new user successfully
  Given I have /user API
  And I have following headers
    | Content-Type |
    | application/json |
  And I have a request body in {"name":"Test User", "email": "[email protected]"}
  When Execute POST request using REST
  Then Validate status code is: 201
  And Validate user response

Delete User API Test

Scenario: Delete an existing user
  Given I have /user/{id} API
  When Execute DELETE request using REST
  Then Validate status code is: 200
  And Validate user deletion response

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Testing Strategy

Unit Tests (UTs)

• Test individual components in isolation using mocked dependencies.
• Tools: JUnit, Mockito.

Integration Tests (ITs)

• Test end-to-end flows with actual database and services.
• Uses Docker containers for MySQL & Redis.
• Runs inside the integration-test profile.

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FAQs

1. Java Version Issues

Execution spotbugs of goal com.github.spotbugs:spotbugs-maven-plugin failed: Unsupported class file major version

• Ensure you are running Java 17:

  java -version

• Set Java 17 as default:

  export JAVA_HOME=$(/usr/libexec/java_home -v 17)

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🚀 You're all set! Happy coding!