1 /*
   2  * Copyright (c) 1996, 2013, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 
  26 package java.awt.event;
  27 
  28 import java.util.EventListener;
  29 
  30 /**
  31  * The listener interface for receiving component events.
  32  * The class that is interested in processing a component event
  33  * either implements this interface (and all the methods it
  34  * contains) or extends the abstract <code>ComponentAdapter</code> class
  35  * (overriding only the methods of interest).
  36  * The listener object created from that class is then registered with a
  37  * component using the component's <code>addComponentListener</code>
  38  * method. When the component's size, location, or visibility
  39  * changes, the relevant method in the listener object is invoked,
  40  * and the <code>ComponentEvent</code> is passed to it.
  41  * <P>
  42  * Component events are provided for notification purposes ONLY;
  43  * The AWT will automatically handle component moves and resizes
  44  * internally so that GUI layout works properly regardless of
  45  * whether a program registers a <code>ComponentListener</code> or not.
  46  *
  47  * @see ComponentAdapter
  48  * @see ComponentEvent
  49  * @see <a href="http://docs.oracle.com/javase/tutorial/uiswing/events/componentlistener.html">Tutorial: Writing a Component Listener</a>
  50  *
  51  * @author Carl Quinn
  52  * @since 1.1
  53  */
  54 public interface ComponentListener extends EventListener {
  55     /**
  56      * Invoked when the component's size changes.
  57      * @param e the event to be processed
  58      */
  59     public void componentResized(ComponentEvent e);
  60 
  61     /**
  62      * Invoked when the component's position changes.
  63      * @param e the event to be processed
  64      */
  65     public void componentMoved(ComponentEvent e);
  66 
  67     /**
  68      * Invoked when the component has been made visible.
  69      * @param e the event to be processed
  70      */
  71     public void componentShown(ComponentEvent e);
  72 
  73     /**
  74      * Invoked when the component has been made invisible.
  75      * @param e the event to be processed
  76      */
  77     public void componentHidden(ComponentEvent e);
  78 }