This interface defines the
update( ) method required for an object to observe
subclasses of Observable. An
Observer registers interest in an
Observable object by calling the
addObserver( ) method of
Observable. Observer objects
that have been registered in this way have their update(
) methods invoked by the Observable when
that object has changed. This interface is conceptually similar to, but less commonly used
than, the EventListener interface and its various
event-specific subinterfaces. public interface Observer {
// Public Instance Methods
void update (Observable o , Object arg );
}
Passed To
Observable.{addObserver( ),
deleteObserver( )} |