Java ApplicationEvents: Difference between @EventListener annotation and ApplicationListener interface

Question

I am using Java ApplicationEvents to publish and then subscribe listen to an event. What is the difference between @EventListener annotation and ApplicationListener interface. Any differences, or the same functionality?

Resource: https://reflectoring.io/spring-boot-application-events-explained/

Method 1:

@Component
class UserRemovedListener {

  @EventListener(condition = "#event.name eq 'reflectoring'")
  void handleConditionalListener(UserRemovedEvent event) {
    // handle UserRemovedEvent
  }
}

Method 2:

@Component
class UserCreatedListener implements ApplicationListener<UserCreatedEvent> {

  @Override
  public void onApplicationEvent(UserCreatedEvent event) {
    // handle UserCreatedEvent
  }
}

Answer 1

Based on the document, they are almost the same

There are two ways to define a listener. We can either use the @EventListener annotation or implement the ApplicationListener interface. In either case, the listener class has to be managed by Spring.Blockquote

But if you use @EvenListener, it will automatically register the ApplicationListener. The whole quote are:

Starting with Spring 4.1 it’s now possible to simply annotate a method of a managed bean with @EventListener to automatically register an ApplicationListener matching the signature of the method

In the official site, the doc also explains that the annotation make it easier to use + shorter. The link should be: https://docs.spring.io/spring-framework/docs/current/javadoc-api/org/springframework/context/event/EventListener.html

https://docs.spring.io/spring-framework/docs/current/javadoc-api/org/springframework/context/ApplicationListener.html

Hope this help.