1 /*
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   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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   5  * This code is free software; you can redistribute it and/or modify it
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   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
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  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
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  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 
  26 package java.awt.event;
  27 
  28 /**
  29  * An abstract adapter class for receiving ancestor moved and resized events.
  30  * The methods in this class are empty. This class exists as a
  31  * convenience for creating listener objects.
  32  * <p>
  33  * Extend this class and override the method for the event of interest. (If
  34  * you implement the {@code HierarchyBoundsListener} interface, you have
  35  * to define both methods in it. This abstract class defines null methods for
  36  * them both, so you only have to define the method for the event you care
  37  * about.)
  38  * <p>
  39  * Create a listener object using your class and then register it with a
  40  * Component using the Component's {@code addHierarchyBoundsListener}
  41  * method. When the hierarchy to which the Component belongs changes by
  42  * resize or movement of an ancestor, the relevant method in the listener
  43  * object is invoked, and the {@code HierarchyEvent} is passed to it.
  44  *
  45  * @author      David Mendenhall
  46  * @see         HierarchyBoundsListener
  47  * @see         HierarchyEvent
  48  * @since       1.3
  49  */
  50 public abstract class HierarchyBoundsAdapter implements HierarchyBoundsListener
  51 {
  52     /**
  53      * Constructs a {@code HierarchyBoundsAdapter}.
  54      */
  55     protected HierarchyBoundsAdapter() {}
  56 
  57     /**
  58      * Called when an ancestor of the source is moved.
  59      */
  60     public void ancestorMoved(HierarchyEvent e) {}
  61 
  62     /**
  63      * Called when an ancestor of the source is resized.
  64      */
  65     public void ancestorResized(HierarchyEvent e) {}
  66 }