1 /*
   2  * Copyright (c) 1996, 2020, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
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   7  * published by the Free Software Foundation.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
  10  *
  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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  23  * questions.
  24  */
  25 
  26 package java.awt.event;
  27 
  28 /**
  29  * An abstract adapter class for receiving component events.
  30  * The methods in this class are empty. This class exists as
  31  * convenience for creating listener objects.
  32  * <P>
  33  * Extend this class to create a {@code ComponentEvent} listener
  34  * and override the methods for the events of interest. (If you implement the
  35  * {@code ComponentListener} interface, you have to define all of
  36  * the methods in it. This abstract class defines null methods for them
  37  * all, so you can only have to define methods for events you care about.)
  38  * <P>
  39  * Create a listener object using your class and then register it with a
  40  * component using the component's {@code addComponentListener}
  41  * method. When the component's size, location, or visibility
  42  * changes, the relevant method in the listener object is invoked,
  43  * and the {@code ComponentEvent} is passed to it.
  44  *
  45  * @see ComponentEvent
  46  * @see ComponentListener
  47  * @see <a href="https://docs.oracle.com/javase/tutorial/uiswing/events/componentlistener.html">Tutorial: Writing a Component Listener</a>
  48  *
  49  * @author Carl Quinn
  50  * @since 1.1
  51  */
  52 public abstract class ComponentAdapter implements ComponentListener {
  53 
  54     /**
  55      * Constructs a {@code ComponentAdapter}.
  56      */
  57     protected ComponentAdapter() {}
  58 
  59     /**
  60      * Invoked when the component's size changes.
  61      */
  62     public void componentResized(ComponentEvent e) {}
  63 
  64     /**
  65      * Invoked when the component's position changes.
  66      */
  67     public void componentMoved(ComponentEvent e) {}
  68 
  69     /**
  70      * Invoked when the component has been made visible.
  71      */
  72     public void componentShown(ComponentEvent e) {}
  73 
  74     /**
  75      * Invoked when the component has been made invisible.
  76      */
  77     public void componentHidden(ComponentEvent e) {}
  78 }