Name
Observer
Synopsis
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( )}
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