Source for java.awt.dnd.DropTargetContext

   1: /* DropTargetContext.java --
   2:    Copyright (C) 2002, 2003, 2004, 2005, 2006 Free Software Foundation
   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., 51 Franklin Street, Fifth Floor, Boston, MA
  19: 02110-1301 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: package java.awt.dnd;
  39: 
  40: import java.awt.Component;
  41: import java.awt.datatransfer.DataFlavor;
  42: import java.awt.datatransfer.Transferable;
  43: import java.awt.datatransfer.UnsupportedFlavorException;
  44: import java.awt.dnd.peer.DropTargetContextPeer;
  45: import java.io.IOException;
  46: import java.io.Serializable;
  47: import java.util.Arrays;
  48: import java.util.List;
  49: 
  50: /**
  51:  * @author Michael Koch (konqueror@gmx.de)
  52:  * @author Andrew John Hughes (gnu_andrew@member.fsf.org)
  53:  * @since 1.2
  54:  */
  55: public class DropTargetContext implements Serializable
  56: {
  57:   static final long serialVersionUID = -634158968993743371L;
  58: 
  59:   protected class TransferableProxy implements Transferable
  60:   {
  61:     protected boolean isLocal;
  62:     protected Transferable transferable;
  63: 
  64:     TransferableProxy(Transferable t, boolean local)
  65:     {
  66:       this.transferable = t;
  67:       this.isLocal = local;
  68:     }
  69:     
  70:     public DataFlavor[] getTransferDataFlavors()
  71:     {
  72:       return transferable.getTransferDataFlavors();
  73:     }
  74: 
  75:     public boolean isDataFlavorSupported(DataFlavor flavor)
  76:     {
  77:       return transferable.isDataFlavorSupported(flavor);
  78:     }
  79: 
  80:     public Object getTransferData(DataFlavor flavor)
  81:       throws UnsupportedFlavorException, IOException
  82:     {
  83:       return transferable.getTransferData (flavor);
  84:     }
  85:   }
  86: 
  87:   private DropTarget dropTarget;
  88:   private int targetActions;
  89:   private DropTargetContextPeer dtcp;
  90: 
  91:   // package private
  92:   DropTargetContext(DropTarget dropTarget)
  93:   {
  94:     this.dropTarget = dropTarget;
  95:   }
  96: 
  97:   public DropTarget getDropTarget()
  98:   {
  99:     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