This module contains practical examples of common Spring Boot development scenarios.

• Location: src/main/resources/application.properties and application-development.properties.
• Approach: Use a common properties file for shared configuration and profile-specific files (e.g., -development, -production) for environment-dependent settings. Active profiles are set via spring.profiles.active.

• Location: com.froyo.mlt.controller.InvoiceV1Controller.
• Approach: Leverage URL versioning (e.g., /api/v1/invoices) to ensure backward compatibility as the API evolves.

• Location: com.froyo.mlt.service.ProductService.
• Approach: Use @CachePut to update the cache synchronously whenever the database is modified, ensuring the cache always reflects the latest state.

• Location: com.froyo.mlt.controller.GlobalReactiveExceptionHandler.
• Approach: Use @ControllerAdvice in a Spring WebFlux application with @ExceptionHandler to catch and process asynchronous errors gracefully.

• Location: com.froyo.mlt.repository.OrderRepository.
• Approach: Use the @Query annotation with JPQL or native SQL to implement complex data retrieval needs that involve multiple criteria, sorting, and pagination.

• Location: com.froyo.mlt.service.OrderMessagePublisher.
• Approach: Integrate Spring Cloud Stream (with Kafka or RabbitMQ) to enable efficient asynchronous communication and coordination between microservices, enhancing scalability and responsiveness.

• Location: com.froyo.mlt.repository.InventoryRepository.
• Approach: Use @Lock(LockModeType.PESSIMISTIC_WRITE) to manage concurrent access to database entities, ensuring that update operations are serialized to prevent data inconsistencies.

• Location: com.froyo.mlt.config.SecurityConfig.
• Approach: Extend WebSecurityConfigurerAdapter and override the configure(HttpSecurity http) method to define authorized/unauthorized access paths and security filters.

• Location: com.froyo.mlt.model.FinancialAccount.
• Approach: Implement optimistic locking by adding a @Version field to the entity. This prevents the "lost update" problem in concurrent environments without the overhead of heavy database locks.

• Location: com.froyo.mlt.service.StockMarketService.
• Approach: Use the @Async annotation to offload time-consuming tasks to separate threads, preventing performance bottlenecks in the main application flow and ensuring a responsive user experience.