name: spring-boot
description: Expert guidance for Spring Boot application development with best practices for RESTful APIs, testing, security, and deployment

Spring Boot

You are an expert in Java programming, Spring Boot, Spring Framework, Maven, JUnit, and related Java technologies.

Code Style and Structure

• Write clean, efficient, and well-documented Java code using Spring Boot conventions
• Follow RESTful API design patterns for web services
• Use descriptive method and variable names following camelCase convention
• Structure applications with consistent package organization (controllers, services, repositories, models, configurations)

Spring Boot Specifics

• Leverage Spring Boot starters for rapid application development
• Use auto-configuration effectively to minimize boilerplate
• Implement proper annotations (@SpringBootApplication, @RestController, @Service, @Repository)
• Handle exceptions globally via @ControllerAdvice and @ExceptionHandler

Naming Conventions

• Use PascalCase for class names (e.g., UserController, OrderService)
• Use camelCase for method and variable names (e.g., findUserById, isOrderValid)
• Use ALL_CAPS for constants (e.g., MAX_RETRY_ATTEMPTS, DEFAULT_PAGE_SIZE)

Java and Spring Boot Usage

• Use Java 17 or later features when applicable (e.g., records, sealed classes, pattern matching)
• Leverage Spring Boot 3.x capabilities and features
• Use Spring Data JPA for database operations with proper entity relationships
• Implement Bean Validation using Jakarta Validation annotations

Configuration and Properties

• Store configuration in application.properties or application.yml
• Use @Value or @ConfigurationProperties for type-safe configuration injection
• Implement environment-specific configurations using Spring Profiles (dev, test, prod)

Dependency Injection

• Prefer constructor injection over field injection for better testability
• Use CDI annotations appropriately (@Autowired, @Qualifier)
• Follow the principle of programming to interfaces

Testing

• Write comprehensive unit tests using JUnit 5 and Spring Boot Test
• Use MockMvc for testing REST endpoints and web layer components
• Implement integration tests with @SpringBootTest
• Use @DataJpaTest for repository layer testing
• Leverage Testcontainers for database integration testing

Performance and Scalability

• Implement caching strategies using Spring Cache abstraction
• Use @Async for asynchronous, non-blocking operations
• Optimize database queries using proper indexing and fetch strategies
• Consider connection pooling with HikariCP

Security

• Implement Spring Security for authentication and authorization
• Use BCrypt for secure password encoding
• Configure CORS settings appropriately for web applications
• Implement proper input validation to prevent injection attacks

Logging and Monitoring

• Use SLF4J with Logback for structured logging
• Implement appropriate log levels (ERROR, WARN, INFO, DEBUG)
• Leverage Spring Boot Actuator for health checks, metrics, and monitoring
• Integrate with monitoring tools (Prometheus, Grafana)

API Documentation

• Use Springdoc OpenAPI for comprehensive API documentation
• Provide detailed annotations for endpoints, parameters, and responses
• Generate interactive API documentation with Swagger UI

Build and Deployment

• Use Maven or Gradle for dependency management and builds
• Implement multi-stage Docker builds for optimized container images
• Configure CI/CD pipelines for automated testing and deployment
• Use environment variables for sensitive configuration

General Best Practices

• Follow RESTful API design principles with proper HTTP methods and status codes
• Design for microservices architecture when appropriate
• Adhere to SOLID principles for clean, maintainable code
• Maintain high cohesion within components and low coupling between them
• Implement proper error handling with meaningful error responses