libjava/java/awt/dnd/DragSourceAdapter.java

   1 /* DragSourceAdapter.java -- drag-and-drop listener adapter
   2    Copyright (C) 2002 Free Software Foundation, Inc.
   3
   4 This file is part of GNU Classpath.
   5
   6 GNU Classpath is free software; you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation; either version 2, or (at your option)
   9 any later version.
  10
  11 GNU Classpath is distributed in the hope that it will be useful, but
  12 WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14 General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GNU Classpath; see the file COPYING.  If not, write to the
  18 Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  19 02111-1307 USA.
  20
  21 Linking this library statically or dynamically with other modules is
  22 making a combined work based on this library.  Thus, the terms and
  23 conditions of the GNU General Public License cover the whole
  24 combination.
  25
  26 As a special exception, the copyright holders of this library give you
  27 permission to link this library with independent modules to produce an
  28 executable, regardless of the license terms of these independent
  29 modules, and to copy and distribute the resulting executable under
  30 terms of your choice, provided that you also meet, for each linked
  31 independent module, the terms and conditions of the license of that
  32 module.  An independent module is a module which is not derived from
  33 or based on this library.  If you modify this library, you may extend
  34 this exception to your version of the library, but you are not
  35 obligated to do so.  If you do not wish to do so, delete this
  36 exception statement from your version. */
  37
  38
  39 package java.awt.dnd;
  40
  41 /**
  42  * This class implements <code>DragSourceListener</code> and
  43  * <code>DragSourceMotionListener</code>, and implements all methods
  44  * with empty bodies.  This allows a listener interested in implementing only
  45  * a subset of these interfaces to extend this class and override only the
  46  * desired methods.
  47  *
  48  * @author Eric Blake <ebb9@email.byu.edu>
  49  * @see DragSourceEvent
  50  * @see DragSourceListener
  51  * @see DragSourceMotionListener
  52  * @since 1.4
  53  * @status updated to 1.4
  54  */
  55 public abstract class DragSourceAdapter
  56   implements DragSourceListener, DragSourceMotionListener
  57 {
  58   /**
  59    * Default constructor.
  60    */
  61   public DragSourceAdapter()
  62   {
  63   }
  64
  65   /**
  66    * Called when the cursor hotspot enters a drop site which will accept the
  67    * drag.
  68    *
  69    * @param e the event
  70    */
  71   public void dragEnter(DragSourceDragEvent e)
  72   {
  73   }
  74
  75   /**
  76    * Called when the cursor hotspot moves inside of a drop site which will
  77    * accept the drag.
  78    *
  79    * @param e the event
  80    */
  81   public void dragOver(DragSourceDragEvent e)
  82   {
  83   }
  84
  85   /**
  86    * Called whenever the mouse is moved during a drag-and-drop operation.
  87    *
  88    * @param e the event
  89    */
  90   public void dragMouseMoved(DragSourceDragEvent e)
  91   {
  92   }
  93
  94   /**
  95    * Called when the user modifies the drop gesture. This is often the case
  96    * when additional mouse or key events are received during the drag.
  97    *
  98    * @param e the event
  99    */
 100   public void dropActionChanged(DragSourceDragEvent e)
 101   {
 102   }
 103
 104   /**
 105    * Called when the cursor hotspot moves outside of a drop site which will
 106    * accept the drag. This could also happen if the drop site is no longer
 107    * active, or no longer accepts the drag.
 108    *
 109    * @param e the event
 110    */
 111   public void dragExit(DragSourceEvent e)
 112   {
 113   }
 114
 115   /**
 116    * Called when the drag and drop operation is complete. After this event,
 117    * <code>getDropSuccess</code> of the event is valid, and
 118    * <code>getDropAction</code> holds the action requested by the drop site.
 119    * Furthermore, the <code>DragSourceContext</code> is invalidated.
 120    *
 121    * @param e the event
 122    */
 123   public void dragDropEnd(DragSourceDropEvent e)
 124   {
 125   }
 126 } // class DragSourceAdapter