Module java.base

Package java.util

Interface Observer

@Deprecated(since="9")
public interface Observer

Deprecated.

This interface has been deprecated. See the Observable class for further information.

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

Since:

1.0

See Also:

• Observable

Method Summary

Modifier and Type	Method	Description
void	update(Observable o, Object arg)	Deprecated. This method is called whenever the observed object is changed.

Method Details

update

void update(Observable o,
 Object arg)

Deprecated.

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.