/* * Copyright (c) 1996, 2006, Oracle and/or its affiliates. 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. Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.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. *

* Extend this class to create a FocusEvent listener * and override the methods for the events of interest. (If you implement the * FocusListener 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.) *

* Create a listener object using the extended class and then register it with * a component using the component's addFocusListener * method. When the component gains or loses the keyboard focus, * the relevant method in the listener object is invoked, * and the FocusEvent is passed to it. * * @see FocusEvent * @see FocusListener * @see Tutorial: Writing a Focus Listener * * @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) {} }