Where to put @Bean in Spring Boot?

Question

I am wondering what the best place would be for a Spring Boot app to register additional beans. I have a Main class that is annotated with @SpringBootApplication

Answer 1

It depends on where the main class is located which has generally @SpringBootApplication annotations. You can annotate this main class with @ComponentScan(basePackageClasses = HelloWorld.class). Here HelloWorld has bean definitions annotated with @Beans and the class is annotated with @Configurations.

Spring container will scan all the sub-packages of the class specified in @ComponentScan arguments. You can also give wild card entries instead of class name.

Ex: 

@SpringBootApplication
@ComponentScan(basePackageClasses = HelloWorld.class)
public class DemoApplication extends SpringBootServletInitializer {

     public static void main(String[] args) {
          SpringApplication.run(DemoApplication.class);
      }

}

**Bean Class:**

@Configuration
public class HelloWorld {

    @Bean
    public TweetUserSevice tweetUserSevice() {
        return new TweetUserSeviceImpl();
    }

}