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:

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.

© 1993, 2025, Oracle and/or its affiliates. All rights reserved.
Documentation extracted from Debian's OpenJDK Development Kit package.
Licensed under the GNU General Public License, version 2, with the Classpath Exception.
Various third party code in OpenJDK is licensed under different licenses (see Debian package).
Java and OpenJDK are trademarks or registered trademarks of Oracle and/or its affiliates.