Handle the event in this instance. This is the second half of {@link Event#dispatch(Handler)}. The method must invoke a concrete onXxx method for the given event, or invoke it's {@link #onUnhandled(Event)} method if the {@link EventType} of the event is not recognized by the handler. <p> <b>Note:</b> The handler is not supposed to invoke the {@link #handle(Event)} method on it's {@link #children()}, that is the responsibility of the {@link Event#dispatch(Handler)}
Handler