What is the use of the @Configuration in Springboot

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@Configuration is an annotation in Spring Boot that indicates a class is a source of bean definitions. It is used to define beans and their dependencies in a Spring application context. The Spring container processes the annotated class to generate and manage beans during runtime.

The @Configuration annotation is applied to classes that contain bean definitions. Within these classes, methods are annotated with @Bean to define individual beans. These beans are then managed by the Spring IoC (Inversion of Control) container.

Example

Here’s an example of how to use @Configuration in a Spring Boot application:

1. Define a Configuration Class:

Create a class and annotate it with @Configuration to indicate that it contains bean definitions.

   import org.springframework.context.annotation.Bean;
   import org.springframework.context.annotation.Configuration;
@Configuration  

public class AppConfig {

@Bean
public MyService myService() {
return new MyServiceImpl();
}

@Bean
public MyRepository myRepository() {
return new MyRepositoryImpl();
}


}

In this example:

- The AppConfig class is annotated with @Configuration, indicating that it contains bean definitions.

- The myService and myRepository methods are annotated with @Bean, indicating that they return beans to be managed by the Spring container.

2. Use the Configured Beans:

These beans can now be injected into other components using Spring’s dependency injection mechanism.

   import org.springframework.beans.factory.annotation.Autowired;
   import org.springframework.stereotype.Component;
@Component  

public class MyComponent {

private final MyService myService;
private final MyRepository myRepository;

@Autowired
public MyComponent(MyService myService, MyRepository myRepository) {
this.myService = myService;
this.myRepository = myRepository;
}

public void doSomething() {
// Use myService and myRepository
}


}

In this example:

- The MyComponent class uses dependency injection to get instances of MyService and MyRepository.

- Spring automatically injects the beans defined in the AppConfig class.

Summary:

The @Configuration annotation in Spring Boot is used to define and configure beans in an application context. By annotating a class with @Configuration and its methods with @Bean, you can centralize and manage bean creation and configuration, making your application setup more modular, maintainable, and testable.