/*

 * Copyright 1996-2006 Sun Microsystems, Inc.  All Rights Reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Sun designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Sun in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,

 * CA 95054 USA or visit www.sun.com if you need additional information or

 * have any questions.

 */

package java.awt.event;

/**

 * An abstract adapter class for receiving keyboard focus events.

 * The methods in this class are empty. This class exists as

 * convenience for creating listener objects.

 * <P>

 * Extend this class to create a <code>FocusEvent</code> listener

 * and override the methods for the events of interest. (If you implement the

 * <code>FocusListener</code> interface, you have to define all of

 * the methods in it. This abstract class defines null methods for them

 * all, so you can only have to define methods for events you care about.)

 * <P>

 * Create a listener object using the extended class and then register it with

 * a component using the component's <code>addFocusListener</code>

 * method. When the component gains or loses the keyboard focus,

 * the relevant method in the listener object is invoked,

 * and the <code>FocusEvent</code> is passed to it.

 *

 * @see FocusEvent

 * @see FocusListener

 * @see <a href="http://java.sun.com/docs/books/tutorial/post1.0/ui/focuslistener.html">Tutorial: Writing a Focus Listener</a>

 *

 * @author Carl Quinn

 * @since 1.1

 */

public abstract class FocusAdapter implements FocusListener {

    /**

     * Invoked when a component gains the keyboard focus.

     */

    public void focusGained(FocusEvent e) {}

    /**

     * Invoked when a component loses the keyboard focus.

     */

    public void focusLost(FocusEvent e) {}

}