Source for javax.swing.TransferHandler

   1: /* TransferHandler.java --
   2:    Copyright (C) 2004, 2005 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., 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: 
  39: package javax.swing;
  40: 
  41: import java.awt.datatransfer.Clipboard;
  42: import java.awt.datatransfer.DataFlavor;
  43: import java.awt.datatransfer.Transferable;
  44: import java.awt.event.ActionEvent;
  45: import java.awt.event.InputEvent;
  46: import java.awt.Toolkit;
  47: import java.io.Serializable;
  48: 
  49: public class TransferHandler implements Serializable
  50: {
  51:   static class TransferAction extends AbstractAction
  52:   {
  53:     private String command;
  54: 
  55:     public TransferAction(String command)
  56:     {
  57:       super(command);
  58:       this.command = command;
  59:     }
  60:     
  61:     public void actionPerformed(ActionEvent event)
  62:     {
  63:       JComponent component = (JComponent) event.getSource();
  64:       TransferHandler transferHandler = component.getTransferHandler();
  65:       Clipboard clipboard = getClipboard(component);
  66: 
  67:       if (clipboard == null)
  68:     {
  69:       // Access denied!
  70:       Toolkit.getDefaultToolkit().beep();
  71:       return;
  72:     }
  73: 
  74:       if (command.equals(COMMAND_COPY))
  75:     transferHandler.exportToClipboard(component, clipboard, COPY);
  76:       else if (command.equals(COMMAND_CUT))
  77:     transferHandler.exportToClipboard(component, clipboard, MOVE);
  78:       else if (command.equals(COMMAND_PASTE))
  79:     {
  80:       Transferable transferable = clipboard.getContents(null);
  81: 
  82:       if (transferable != null)
  83:         transferHandler.importData(component, transferable);
  84:     }
  85:     }
  86:   
  87:     /**
  88:      * Get the system cliboard or null if the caller isn't allowed to
  89:      * access the system clipboard.
  90:      * 
  91:      * @param component a component, used to get the toolkit.
  92:      * @return the clipboard
  93:      */
  94:     private static Clipboard getClipboard(JComponent component)
  95:     {
  96:       try
  97:     {
  98:       return component.getToolkit().getSystemClipboard();
  99:     }
 100:       catch (SecurityException se)
 101:     {
 102:       return null;
 103:     }
 104:     }
 105:   }
 106:   
 107:   private static final long serialVersionUID = -967749805571669910L;
 108: 
 109:   private static final String COMMAND_COPY = "copy";
 110:   private static final String COMMAND_CUT = "cut";
 111:   private static final String COMMAND_PASTE = "paste";
 112:   
 113:   public static final int NONE = 0;
 114:   public static final int COPY = 1;
 115:   public static final int MOVE = 2;
 116:   public static final int COPY_OR_MOVE = 3;
 117: 
 118:   private static Action copyAction = new TransferAction(COMMAND_COPY);
 119:   private static Action cutAction = new TransferAction(COMMAND_CUT);
 120:   private static Action pasteAction = new TransferAction(COMMAND_PASTE);
 121:   
 122:   private int sourceActions;
 123:   private Icon visualRepresentation;
 124:   
 125:   public static Action getCopyAction()
 126:   {
 127:     return copyAction;
 128:   }
 129: 
 130:   public static Action getCutAction()
 131:   {
 132:     return cutAction;
 133:   }
 134: 
 135:   public static Action getPasteAction()
 136:   {
 137:     return pasteAction;
 138:   }
 139: 
 140:   protected TransferHandler()
 141:   {
 142:     this.sourceActions = NONE;
 143:   }
 144: 
 145:   public TransferHandler(String property)
 146:   {
 147:     this.sourceActions = property != null ? COPY : NONE;
 148:   }
 149: 
 150:   public boolean canImport (JComponent c, DataFlavor[] flavors)
 151:   {
 152:     return false;
 153:   }
 154: 
 155:   protected Transferable createTransferable(JComponent c) 
 156:   {
 157:     return null;
 158:   }
 159: 
 160:   public void exportAsDrag (JComponent c, InputEvent e, int action) 
 161:   {
 162:     // TODO: Implement this properly
 163:   }
 164: 
 165:   protected void exportDone (JComponent c, Transferable data, int action) 
 166:   {
 167:     // TODO: Implement this properly
 168:   }
 169: 
 170:   public void exportToClipboard(JComponent c, Clipboard clip, int action) 
 171:   {
 172:     // TODO: Implement this properly
 173:   } 
 174: 
 175:   public int getSourceActions (JComponent c)
 176:   {
 177:     return sourceActions;
 178:   }
 179: 
 180:   public Icon getVisualRepresentation (Transferable t)
 181:   {
 182:     return visualRepresentation;
 183:   }
 184: 
 185:   public boolean importData (JComponent c, Transferable t) 
 186:   {
 187:     return false;
 188:   }
 189: }