001    /* DropTargetContext.java --
002       Copyright (C) 2002, 2003, 2004, 2005, 2006 Free Software Foundation
003    
004    This file is part of GNU Classpath.
005    
006    GNU Classpath is free software; you can redistribute it and/or modify
007    it under the terms of the GNU General Public License as published by
008    the Free Software Foundation; either version 2, or (at your option)
009    any later version.
010    
011    GNU Classpath is distributed in the hope that it will be useful, but
012    WITHOUT ANY WARRANTY; without even the implied warranty of
013    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
014    General Public License for more details.
015    
016    You should have received a copy of the GNU General Public License
017    along with GNU Classpath; see the file COPYING.  If not, write to the
018    Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
019    02110-1301 USA.
020    
021    Linking this library statically or dynamically with other modules is
022    making a combined work based on this library.  Thus, the terms and
023    conditions of the GNU General Public License cover the whole
024    combination.
025    
026    As a special exception, the copyright holders of this library give you
027    permission to link this library with independent modules to produce an
028    executable, regardless of the license terms of these independent
029    modules, and to copy and distribute the resulting executable under
030    terms of your choice, provided that you also meet, for each linked
031    independent module, the terms and conditions of the license of that
032    module.  An independent module is a module which is not derived from
033    or based on this library.  If you modify this library, you may extend
034    this exception to your version of the library, but you are not
035    obligated to do so.  If you do not wish to do so, delete this
036    exception statement from your version. */
037    
038    package java.awt.dnd;
039    
040    import java.awt.Component;
041    import java.awt.datatransfer.DataFlavor;
042    import java.awt.datatransfer.Transferable;
043    import java.awt.datatransfer.UnsupportedFlavorException;
044    import java.awt.dnd.peer.DropTargetContextPeer;
045    import java.io.IOException;
046    import java.io.Serializable;
047    import java.util.Arrays;
048    import java.util.List;
049    
050    /**
051     * @author Michael Koch (konqueror@gmx.de)
052     * @author Andrew John Hughes (gnu_andrew@member.fsf.org)
053     * @since 1.2
054     */
055    public class DropTargetContext implements Serializable
056    {
057      static final long serialVersionUID = -634158968993743371L;
058    
059      protected class TransferableProxy implements Transferable
060      {
061        protected boolean isLocal;
062        protected Transferable transferable;
063    
064        TransferableProxy(Transferable t, boolean local)
065        {
066          this.transferable = t;
067          this.isLocal = local;
068        }
069    
070        public DataFlavor[] getTransferDataFlavors()
071        {
072          return transferable.getTransferDataFlavors();
073        }
074    
075        public boolean isDataFlavorSupported(DataFlavor flavor)
076        {
077          return transferable.isDataFlavorSupported(flavor);
078        }
079    
080        public Object getTransferData(DataFlavor flavor)
081          throws UnsupportedFlavorException, IOException
082        {
083          return transferable.getTransferData (flavor);
084        }
085      }
086    
087      private DropTarget dropTarget;
088      private int targetActions;
089      private DropTargetContextPeer dtcp;
090    
091      // package private
092      DropTargetContext(DropTarget dropTarget)
093      {
094        this.dropTarget = dropTarget;
095      }
096    
097      public DropTarget getDropTarget()
098      {
099        return dropTarget;
100      }
101    
102      public Component getComponent()
103      {
104        return dropTarget.getComponent();
105      }
106    
107      public void addNotify(DropTargetContextPeer dtcp)
108      {
109        this.dtcp = dtcp;
110      }
111    
112      public void removeNotify()
113      {
114        this.dtcp = null;
115      }
116    
117      protected void setTargetActions(int actions)
118      {
119        targetActions = actions;
120      }
121    
122      protected int getTargetActions()
123      {
124        return targetActions;
125      }
126    
127      /**
128       * Signals that the drop is completed.
129       *
130       * @exception InvalidDnDOperationException If a drop is not outstanding.
131       */
132      public void dropComplete (boolean success)
133      {
134        if (dtcp != null)
135          dtcp.dropComplete(success);
136      }
137    
138      protected void acceptDrag (int dragOperation)
139      {
140        if (dtcp != null)
141          dtcp.acceptDrag(dragOperation);
142      }
143    
144      protected void rejectDrag ()
145      {
146        if (dtcp != null)
147          dtcp.rejectDrag();
148      }
149    
150      protected void acceptDrop (int dropOperation)
151      {
152        if (dtcp != null)
153          dtcp.acceptDrop(dropOperation);
154      }
155    
156      protected void rejectDrop ()
157      {
158        if (dtcp != null)
159          dtcp.rejectDrop();
160      }
161    
162      protected DataFlavor[] getCurrentDataFlavors ()
163      {
164        if (dtcp != null)
165          dtcp.getTransferDataFlavors();
166        return null;
167      }
168    
169      protected List<DataFlavor> getCurrentDataFlavorsAsList ()
170      {
171        return Arrays.asList(getCurrentDataFlavors ());
172      }
173    
174      protected boolean isDataFlavorSupported (DataFlavor flavor)
175      {
176        return getCurrentDataFlavorsAsList().contains (flavor);
177      }
178    
179      /**
180       * Return the <code>Transferable</code> operandof this operation.
181       *
182       * @exception InvalidDnDOperationException If a drag is not outstanding.
183       */
184      protected Transferable getTransferable()
185        throws InvalidDnDOperationException
186      {
187        // FIXME: Implement this
188        if (dtcp != null)
189          return dtcp.getTransferable();
190        return null;
191      }
192    
193      protected Transferable createTransferableProxy(Transferable t, boolean local)
194      {
195        return new TransferableProxy(t, local);
196      }
197    } // class DropTargetContext