java.util
Interface Observer


public interface Observer

A class can implement the Observer interface when it wants to be informed of changes in observable objects.

Since:
JDK1.0
See Also:
Observable sample code for java.util.Observable definition code for java.util.Observable

Method Summary
 void update sample code for java.util.Observer.update(java.util.Observable, java.lang.Object) definition code for java.util.Observer.update(java.util.Observable, java.lang.Object) (Observable sample code for java.util.Observable definition code for java.util.Observable  o, Object sample code for java.lang.Object definition code for java.lang.Object  arg)
          This method is called whenever the observed object is changed.
 

Method Detail

update sample code for java.util.Observer.update(java.util.Observable, java.lang.Object) definition code for java.util.Observer.update(java.util.Observable, java.lang.Object)

void update(Observable sample code for java.util.Observable definition code for java.util.Observable  o,
            Object sample code for java.lang.Object definition code for java.lang.Object  arg)
This method is called whenever the observed object is changed. An application calls an Observable object's notifyObservers method to have all the object's observers notified of the change.

Parameters:
o - the observable object.
arg - an argument passed to the notifyObservers method.