minwin-gcc-5-2/libjava/classpath/java/util/Observer.java

/* Observer.java -- an object that will be informed of changes in an Observable
   Copyright (C) 1998, 1999, 2001, 2002, 2005  Free Software Foundation, Inc.

This file is part of GNU Classpath.

GNU Classpath is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
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any later version.

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WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
General Public License for more details.

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along with GNU Classpath; see the file COPYING.  If not, write to the
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02110-1301 USA.

Linking this library statically or dynamically with other modules is
making a combined work based on this library.  Thus, the terms and
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As a special exception, the copyright holders of this library give you
permission to link this library with independent modules to produce an
executable, regardless of the license terms of these independent
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independent module, the terms and conditions of the license of that
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package java.util;

/**
 * Interface that is implemented when a class wants to be informed of changes
 * in Observable objects.
 *
 * @author Warren Levy (warrenl@cygnus.com)
 * @see Observable
 * @status updated to 1.4
 */
public interface Observer
{
  /**
   * This method is called whenever the observable object changes, and has
   * called <code>notifyObservers</code>. The Observable object can pass
   * arbitrary information in the second parameter.
   *
   * @param observable the Observable object that changed
   * @param arg arbitrary information, usually relating to the change
   */
  void update(Observable observable, Object arg);
}