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java.util
Interface Observer

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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

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Method Summary
void	update(Observable o, Object arg) This method is called whenever the observed object is changed.

Method Detail

update

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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Overview Package Class Use Tree Deprecated Index Help		Java™ Platform Standard Ed. 6
PREV CLASS NEXT CLASS	FRAMES NO FRAMES All Classes
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