001 /* FocusListener.java -- listen for focus changes
002 Copyright (C) 1999, 2002, 2005 Free Software Foundation, Inc.
003
004 This file is part of GNU Classpath.
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020
021 Linking this library statically or dynamically with other modules is
022 making a combined work based on this library. Thus, the terms and
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026 As a special exception, the copyright holders of this library give you
027 permission to link this library with independent modules to produce an
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036 exception statement from your version. */
037
038
039 package java.awt.event;
040
041 import java.util.EventListener;
042
043 /**
044 * This interface is for classes that wish to be notified of changes of
045 * keyboard focus for a component. To watch a subset of these events, use a
046 * FocusAdapter.
047 *
048 * @author Aaron M. Renn (arenn@urbanophile.com)
049 * @see FocusAdapter
050 * @see FocusEvent
051 * @since 1.1
052 * @status updated to 1.4
053 */
054 public interface FocusListener extends EventListener
055 {
056 /**
057 * This method is called when a component gains the keyboard focus.
058 *
059 * @param event the <code>FocusEvent</code> indicating that focus was gained
060 */
061 void focusGained(FocusEvent event);
062
063 /**
064 * This method is invoked when a component loses the keyboard focus.
065 *
066 * @param event the <code>FocusEvent</code> indicating that focus was lost
067 */
068 void focusLost(FocusEvent event);
069 } // interface FocusListener