libjava/javax/swing/TransferHandler.java

   1 /* TransferHandler.java --
   2    Copyright (C) 2004 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 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.io.Serializable;
  47
  48 public class TransferHandler implements Serializable
  49 {
  50   static class TransferAction extends AbstractAction
  51   {
  52     private String command;
  53
  54     public TransferAction(String command)
  55     {
  56       this.command = command;
  57     }
  58
  59     public void actionPerformed(ActionEvent event)
  60     {
  61       JComponent component = (JComponent) event.getSource();
  62       TransferHandler transferHandler = component.getTransferHandler();
  63       Clipboard clipboard = getClipboard(component);
  64
  65       if (command.equals(COMMAND_COPY))
  66         transferHandler.exportToClipboard(component, clipboard, COPY);
  67       else if (command.equals(COMMAND_CUT))
  68         transferHandler.exportToClipboard(component, clipboard, MOVE);
  69       else if (command.equals(COMMAND_PASTE))
  70         {
  71           Transferable transferable = clipboard.getContents(null);
  72
  73           if (transferable != null)
  74             transferHandler.importData(component, transferable);
  75         }
  76     }
  77
  78     private static Clipboard getClipboard(JComponent component)
  79     {
  80       SecurityManager sm = System.getSecurityManager();
  81
  82       if (sm != null)
  83         {
  84           try
  85             {
  86               sm.checkSystemClipboardAccess();
  87
  88               // We may access system clipboard.
  89               return component.getToolkit().getSystemClipboard();
  90             }
  91           catch (SecurityException e)
  92             {
  93               // We may not access system clipboard.
  94             }
  95         }
  96
  97       // Create VM-local clipboard if non exists yet.
  98       if (clipboard == null)
  99         clipboard = new Clipboard("Clipboard");
 100
 101       return clipboard;
 102     }
 103   }
 104
 105   private static final long serialVersionUID = -7908749299918704233L;
 106
 107   private static final String COMMAND_COPY = "copy";
 108   private static final String COMMAND_CUT = "cut";
 109   private static final String COMMAND_PASTE = "paste";
 110
 111   public static final int NONE = 0;
 112   public static final int COPY = 1;
 113   public static final int MOVE = 2;
 114   public static final int COPY_OR_MOVE = 3;
 115
 116   private static Action copyAction = new TransferAction(COMMAND_COPY);
 117   private static Action cutAction = new TransferAction(COMMAND_CUT);
 118   private static Action pasteAction = new TransferAction(COMMAND_PASTE);
 119
 120   /**
 121    * Clipboard if system clipboard may not be used.
 122    */
 123   private static Clipboard clipboard;
 124
 125   private int sourceActions;
 126   private Icon visualRepresentation;
 127
 128   public static Action getCopyAction()
 129   {
 130     return copyAction;
 131   }
 132
 133   public static Action getCutAction()
 134   {
 135     return cutAction;
 136   }
 137
 138   public static Action getPasteAction()
 139   {
 140     return pasteAction;
 141   }
 142
 143   protected TransferHandler()
 144   {
 145     this.sourceActions = NONE;
 146   }
 147
 148   public TransferHandler(String property)
 149   {
 150     this.sourceActions = property != null ? COPY : NONE;
 151   }
 152
 153   public boolean canImport (JComponent c, DataFlavor[] flavors)
 154   {
 155     return false;
 156   }
 157
 158   protected Transferable createTransferable(JComponent c)
 159   {
 160     return null;
 161   }
 162
 163   public void exportAsDrag (JComponent c, InputEvent e, int action)
 164   {
 165   }
 166
 167   protected void exportDone (JComponent c, Transferable data, int action)
 168   {
 169   }
 170
 171   public void exportToClipboard(JComponent c, Clipboard clip, int action)
 172   {
 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 }