Registration objects returned when an event handler is bound (e.g. via EventBus#addHandler), used to deregister.

A tip: to make a handler deregister itself try something like the following: <code><pre>new MyHandler() { HandlerRegistration reg = MyEvent.register(eventBus, this);

public void onMyThing(MyEvent event) { {@literal /} do your thing {@literal /} reg.removeHandler(); } }; </pre></code>

abstract class HandlerRegistration {

 /**
  * Deregisters the handler associated with this registration object if the
  * handler is still attached to the event source. If the handler is no longer
  * attached to the event source, this is a no-op.
  */
 void removeHandler();
}