public interface java.util.Observer

java.lang.Object
   |
   +----java.util.Observer

public interface Observer

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

See also:

java.util.Observable

update(Observable, Object)

This method is called whenever the observed object is changed

public abstract void update(Observable o,
                            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.

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