mouseevent - GWT : Difference b/w addMouseOutHandler and addDomHandler -

i want implement onmouseout method hide popup.

what difference b/w 2 approaches..?

1. addmouseouthandler

actionspopup.addmouseouthandler(new mouseouthandler() {                  @override         public void onmouseout(mouseoutevent event) {             actionspopup.hide();         }     });     }); 

2. adddomhandler

 actionspopup.adddomhandler(new mouseouthandler() {                  @override         public void onmouseout(mouseoutevent event) {             actionspopup.hide();         }     });     }, mouseoutevent.gettype()); 

there no real difference. if gwt code of basic widgets (like focuspanel) implementation of addmouseouthandler calls adddomhandler:

public handlerregistration addmouseouthandler(mouseouthandler handler) {     return adddomhandler(handler, mouseoutevent.gettype()); } 

but using hasmouseouthandlers interface, code have more flexibility. example can use @uihandler annotation. or can see widget 'hasmouseouthandlers' instance in order group treatments. way, in signature of object, indicate others developers object can receive type of event.