Adeeshaj
commented
7 months ago In this example, the CarService interface acts as a contract defining the operations that can be performed on cars. While it might seem redundant in this simple example, it's a good practice to use interfaces for services in Spring Boot applications for several reasons:
Abstraction and Decoupling: Interfaces help in abstracting the implementation details. The controller interacts with the CarService interface without needing to know the concrete implementation (CarServiceImpl). This decouples the controller from the implementation, making it easier to change or replace the implementation in the future without affecting the controller.
Testability: Interfaces make it easier to mock dependencies during unit testing. You can create mock implementations of the CarService interface for testing the controller independently.
Scalability and Maintainability: Interfaces provide a clear contract for defining the service layer. If your application grows and you need to add more functionality or alternative implementations, you can easily extend the interface and provide new implementations without touching existing code.
Dependency Injection: Spring Boot uses dependency injection to manage and inject dependencies. By defining the service layer as an interface, Spring Boot can inject the appropriate implementation (CarServiceImpl) wherever CarService is required, promoting loose coupling.
While the example provided is simple and the interface may seem unnecessary, it's a best practice to use interfaces for services in Spring Boot applications to adhere to the principles of abstraction, dependency inversion, and separation of concerns.
Create service classes to handle business logic. Implement methods to perform operations on entities using repository methods.
Implement Controllers: Create REST controllers to handle incoming HTTP requests. Define request mapping annotations (@GetMapping, @PostMapping, @PutMapping, @DeleteMapping) and corresponding methods.
Handle Request and Response: Use @requestbody annotation to handle incoming request payloads in POST and PUT requests. Use ResponseEntity to handle response status codes and bodies.
Handle Validation: Implement validation for incoming requests using annotations like @Valid and @validated. Define custom validation logic if necessary.