1. /*

  2.  * @(#)HierarchyListener.java	1.8 03/12/19

  3.  *

  4.  * Copyright 2004 Sun Microsystems, Inc. All rights reserved.

  5.  * SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.

  6.  */

  7. 

  8. package java.awt.event;

  9. 

  10. import java.util.EventListener;

  11. 

  12. /**

  13.  * The listener interface for receiving hierarchy changed events.

  14.  * The class that is interested in processing a hierarchy changed event

  15.  * should implement this interface.

  16.  * The listener object created from that class is then registered with a

  17.  * Component using the Component's <code>addHierarchyListener</code> 

  18.  * method. When the hierarchy to which the Component belongs changes, the

  19.  * <code>hierarchyChanged</code> method in the listener object is invoked,

  20.  * and the <code>HierarchyEvent</code> is passed to it.

  21.  * <p>

  22.  * Hierarchy events are provided for notification purposes ONLY;

  23.  * The AWT will automatically handle changes to the hierarchy internally so

  24.  * that GUI layout, displayability, and visibility work properly regardless

  25.  * of whether a program registers a <code>HierarchyListener</code> or not.

  26.  *

  27.  * @author	David Mendenhall

  28.  * @version	1.8, 12/19/03

  29.  * @see		HierarchyEvent

  30.  * @since 	1.3

  31.  */

  32. public interface HierarchyListener extends EventListener {

  33.     /**

  34.      * Called when the hierarchy has been changed. To discern the actual

  35.      * type of change, call <code>HierarchyEvent.getChangeFlags()</code>.

  36.      *

  37.      * @see HierarchyEvent#getChangeFlags()

  38.      */

  39.     public void hierarchyChanged(HierarchyEvent e);

  40. }