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3    * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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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).
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25  
26  package java.awt.event;
27  
28  /**
29   * An abstract adapter class for receiving keyboard 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>KeyEvent</code> listener
34   * and override the methods for the events of interest. (If you implement the
35   * <code>KeyListener</code> 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 the extended class and then register it with
40   * a component using the component's <code>addKeyListener</code>
41   * method. When a key is pressed, released, or typed,
42   * the relevant method in the listener object is invoked,
43   * and the <code>KeyEvent</code> is passed to it.
44   *
45   * @author Carl Quinn
46   *
47   * @see KeyEvent
48   * @see KeyListener
49   * @see <a href="http://docs.oracle.com/javase/tutorial/uiswing/events/keylistener.html">Tutorial: Writing a Key Listener</a>
50   *
51   * @since 1.1
52   */
53  public abstract class KeyAdapter implements KeyListener {
54      /**
55       * Invoked when a key has been typed.
56       * This event occurs when a key press is followed by a key release.
57       */
58      public void keyTyped(KeyEvent e) {}
59  
60      /**
61       * Invoked when a key has been pressed.
62       */
63      public void keyPressed(KeyEvent e) {}
64  
65      /**
66       * Invoked when a key has been released.
67       */
68      public void keyReleased(KeyEvent e) {}
69  }