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1 /*
2  * @(#)FocusAdapter.java 1.16 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 /**
11  * An abstract adapter class for receiving keyboard focus events.
12  * The methods in this class are empty. This class exists as
13  * convenience for creating listener objects.
14  * <P>
15  * Extend this class to create a <code>FocusEvent</code> listener
16  * and override the methods for the events of interest. (If you implement the
17  * <code>FocusListener</code> interface, you have to define all of
18  * the methods in it. This abstract class defines null methods for them
19  * all, so you can only have to define methods for events you care about.)
20  * <P>
21  * Create a listener object using the extended class and then register it with
22  * a component using the component's <code>addFocusListener</code>
23  * method. When the component gains or loses the keyboard focus,
24  * the relevant method in the listener object is invoked,
25  * and the <code>FocusEvent</code> is passed to it.
26  *
27  * @see FocusEvent
28  * @see FocusListener
29  * @see <a HREF="http://java.sun.com/docs/books/tutorial/post1.0/ui/focuslistener.html">Tutorial: Writing a Focus Listener</a>
30  * @see <a HREF="http://www.awl.com/cp/javaseries/jcl1_2.html">Reference: The Java Class Libraries (update file)</a>
31  *
32  * @author Carl Quinn
33  * @version 1.16 12/19/03
34  * @since 1.1
35  */
36 public abstract class FocusAdapter implements FocusListener JavaDoc {
37     /**
38      * Invoked when a component gains the keyboard focus.
39      */
40     public void focusGained(FocusEvent JavaDoc e) {}
41
42     /**
43      * Invoked when a component loses the keyboard focus.
44      */
45     public void focusLost(FocusEvent JavaDoc e) {}
46 }
47
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