developing-spring-boot

Spring Boot 3+ project setup (Initializr), REST controllers, Service layer patterns, Exception handling (@ControllerAdvice), Profiles and configuration, Bean validation, Async operations

Build production Spring Boot applications using REST controllers, service layer patterns, exception handling, configuration management, and async operations.

Process

1. Project Setup – Use Spring Initializr or scripts/scaffold.py --name myapp --group-id com.example.
2. REST Controllers – Create @RestController with HTTP methods, constructor injection, DTOs.
3. Service Layer – Implement @Service with @Transactional(readOnly = true) for reads, @Transactional for writes.
4. Exception Handling – Add @RestControllerAdvice with handlers for domain exceptions, MethodArgumentNotValidException, ConstraintViolationException, and generic Exception.
5. Configuration – Use application.yml with profiles (dev, prod), @ConfigurationProperties for type-safe config.
6. Bean Validation – Add @Valid on request bodies, use @NotBlank, @NotNull, @Size, etc. on DTOs.
7. Async – Use @EnableAsync and @Async for long-running operations.

Best Practices

• Use constructor injection instead of field injection
• Use @Transactional(readOnly = true) for read operations
• Use DTOs for API requests/responses (never expose entities)
• Implement @ControllerAdvice for global exception handling
• Use Bean Validation for input validation
• Configure profiles for different environments
• Use @Async for long-running operations
• Follow RESTful conventions, use ResponseEntity for proper HTTP status codes

Anti-Patterns

| Anti-Pattern | Fix | |--------------|-----| | Field injection with @Autowired | Use constructor injection | | Exposing entities directly | Use DTOs | | Missing @Transactional on writes | Add @Transactional | | Synchronous blocking operations | Use @Async | | Hardcoded configuration | Use @ConfigurationProperties | | No exception handling | Implement @ControllerAdvice | | Missing validation | Add Bean Validation | | Not using readOnly = true on reads | Add to read methods |

Bundled Resources

| Resource | Purpose | |----------|---------| | Installation Guide | 5-minute guide: Setup and run | | scripts/utils.py | Project utilities | | scripts/validate.py | Verify project follows skill patterns | | REST API Patterns | references/spring-patterns.json |

When to Use

This skill should be used when strict adherence to the defined process is required.

Prerequisites

• Basic understanding of the agent factory context.
• Access to the necessary tools and resources.