polishing

org.springframework.context/src/main/java/org/springframework/context/ApplicationListener.java

@@ -23,8 +23,14 @@ import java.util.EventListener;
  * Based on the standard <code>java.util.EventListener</code> interface
  * for the Observer design pattern.
  *
+ * <p>As of Spring 3.0, an ApplicationListener can generically declare the event type
+ * that it is interested in. When registered with a Spring ApplicationContext, events
+ * will be filtered accordingly, with the listener getting invoked for matching event
+ * objects only.
+ *
  * @author Rod Johnson
  * @author Juergen Hoeller
+ * @param <E> the specific ApplicationEvent subclass to listen to
  * @see org.springframework.context.event.ApplicationEventMulticaster
  */
 public interface ApplicationListener<E extends ApplicationEvent> extends EventListener {