| /* |
| * Copyright (c) 1996, 2013, 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; |
| |
| import java.util.EventListener; |
| |
| /** |
| * The listener interface for receiving keyboard focus events on |
| * a component. |
| * The class that is interested in processing a focus event |
| * either implements this interface (and all the methods it |
| * contains) or extends the abstract {@code FocusAdapter} class |
| * (overriding only the methods of interest). |
| * The listener object created from that class is then registered with a |
| * component using the component's {@code addFocusListener} |
| * method. When the component gains or loses the keyboard focus, |
| * the relevant method in the listener object |
| * is invoked, and the {@code FocusEvent} is passed to it. |
| * |
| * @see FocusAdapter |
| * @see FocusEvent |
| * @see <a href="http://docs.oracle.com/javase/tutorial/uiswing/events/focuslistener.html">Tutorial: Writing a Focus Listener</a> |
| * |
| * @author Carl Quinn |
| * @since 1.1 |
| */ |
| public interface FocusListener extends EventListener { |
| |
| /** |
| * Invoked when a component gains the keyboard focus. |
| * @param e the event to be processed |
| */ |
| public void focusGained(FocusEvent e); |
| |
| /** |
| * Invoked when a component loses the keyboard focus. |
| * @param e the event to be processed |
| */ |
| public void focusLost(FocusEvent e); |
| } |