001/* DragSourceAdapter.java -- drag-and-drop listener adapter
002   Copyright (C) 2002, 2005  Free Software Foundation, Inc.
003
004This file is part of GNU Classpath.
005
006GNU Classpath is free software; you can redistribute it and/or modify
007it under the terms of the GNU General Public License as published by
008the Free Software Foundation; either version 2, or (at your option)
009any later version.
010
011GNU Classpath is distributed in the hope that it will be useful, but
012WITHOUT ANY WARRANTY; without even the implied warranty of
013MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
014General Public License for more details.
015
016You should have received a copy of the GNU General Public License
017along with GNU Classpath; see the file COPYING.  If not, write to the
018Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
01902110-1301 USA.
020
021Linking this library statically or dynamically with other modules is
022making a combined work based on this library.  Thus, the terms and
023conditions of the GNU General Public License cover the whole
024combination.
025
026As a special exception, the copyright holders of this library give you
027permission to link this library with independent modules to produce an
028executable, regardless of the license terms of these independent
029modules, and to copy and distribute the resulting executable under
030terms of your choice, provided that you also meet, for each linked
031independent module, the terms and conditions of the license of that
032module.  An independent module is a module which is not derived from
033or based on this library.  If you modify this library, you may extend
034this exception to your version of the library, but you are not
035obligated to do so.  If you do not wish to do so, delete this
036exception statement from your version. */
037
038
039package java.awt.dnd;
040
041/**
042 * This class implements <code>DragSourceListener</code> and
043 * <code>DragSourceMotionListener</code>, and implements all methods
044 * with empty bodies.  This allows a listener interested in implementing only
045 * a subset of these interfaces to extend this class and override only the
046 * desired methods.
047 *
048 * @author Eric Blake (ebb9@email.byu.edu)
049 * @see DragSourceEvent
050 * @see DragSourceListener
051 * @see DragSourceMotionListener
052 * @since 1.4
053 * @status updated to 1.4
054 */
055public abstract class DragSourceAdapter
056  implements DragSourceListener, DragSourceMotionListener
057{
058  /**
059   * Default constructor.
060   */
061  public DragSourceAdapter()
062  {
063  }
064
065  /**
066   * Called when the cursor hotspot enters a drop site which will accept the
067   * drag.
068   *
069   * @param e the event
070   */
071  public void dragEnter(DragSourceDragEvent e)
072  {
073  }
074
075  /**
076   * Called when the cursor hotspot moves inside of a drop site which will
077   * accept the drag.
078   *
079   * @param e the event
080   */
081  public void dragOver(DragSourceDragEvent e)
082  {
083  }
084
085  /**
086   * Called whenever the mouse is moved during a drag-and-drop operation.
087   *
088   * @param e the event
089   */
090  public void dragMouseMoved(DragSourceDragEvent e)
091  {
092  }
093
094  /**
095   * Called when the user modifies the drop gesture. This is often the case
096   * when additional mouse or key events are received during the drag.
097   *
098   * @param e the event
099   */
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