1 /* Clipboard.java -- Class for transferring data via cut and paste. 2 Copyright (C) 1999, 2001, 2005, 2006 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 java.awt.datatransfer; 40 41 import java.io.IOException; 42 import java.util.ArrayList; 43 44 /** 45 * This class allows data to be transferred using a cut and paste type 46 * mechanism. 47 * 48 * @author Aaron M. Renn (arenn@urbanophile.com) 49 * @author Mark J. Wielaard (mark@klomp.org) 50 */ 51 public class Clipboard 52 { 53 /** 54 * The data currently on this clipboard. For use by 55 * subclasses. Also returned by the public method getContents(). 56 */ 57 protected Transferable contents; 58 59 /** 60 * The owner of this clipboard. 61 */ 62 protected ClipboardOwner owner; 63 64 // The clipboard name 65 private final String name; 66 67 // The flavor listeners (most likely small). 68 private final ArrayList listeners = new ArrayList(3); 69 70 /** 71 * Initializes a new instance of <code>Clipboard</code> with the 72 * specified name. 73 * 74 * @param name The clipboard name. 75 */ Clipboard(String name)76 public Clipboard(String name) 77 { 78 this.name = name; 79 } 80 81 /** 82 * Returns the name of the clipboard. 83 */ getName()84 public String getName() 85 { 86 return name; 87 } 88 89 /** 90 * Returns the contents of the clipboard. 91 * 92 * @param requestor The object requesting the contents. This 93 * implementation ignores this parameter. 94 * 95 * @exception IllegalStateException If the clipboard is currently unavailable 96 */ getContents(Object requestor)97 public synchronized Transferable getContents(Object requestor) 98 { 99 return contents; 100 } 101 102 /** 103 * Sets the content and owner of this clipboard. If the given owner 104 * is different from the current owner then <code>lostOwnership()</code> 105 * is called on the current owner with the old contents of the given 106 * clipboard. 107 * 108 * @param contents The new clipboard contents. 109 * @param owner The new clipboard owner 110 * 111 * @exception IllegalStateException If the clipboard is currently unavailable 112 */ setContents(Transferable contents, ClipboardOwner owner)113 public synchronized void setContents(Transferable contents, 114 ClipboardOwner owner) 115 { 116 Transferable oldContents = getContents(null); 117 this.contents = contents; 118 if (this.owner != owner) 119 { 120 ClipboardOwner oldOwner = this.owner; 121 this.owner = owner; 122 if (oldOwner != null) 123 oldOwner.lostOwnership(this, oldContents); 124 } 125 126 FlavorListener[] fs = getFlavorListeners(); 127 if (fs.length > 0) 128 { 129 // We are a bit optimistic here. We assume DataFlavors will be 130 // given in the same order. If the number of flavors is 131 // different or the order of the DataFlavors in the list then 132 // fire a change event. 133 boolean newFlavors = ((contents != null && oldContents == null) 134 || (contents == null && oldContents != null)); 135 if (!newFlavors && contents != null && oldContents != null) 136 { 137 DataFlavor[] df1 = contents.getTransferDataFlavors(); 138 DataFlavor[] df2 = oldContents.getTransferDataFlavors(); 139 newFlavors = df1.length != df2.length; 140 141 for (int i = 0; !newFlavors && i < df1.length; i++) 142 newFlavors = !df1[i].equals(df2[i]); 143 } 144 145 if (newFlavors) 146 { 147 FlavorEvent e = new FlavorEvent(this); 148 for (int i = 0; i < fs.length; i++) 149 fs[i].flavorsChanged(e); 150 } 151 } 152 } 153 getAvailableDataFlavors()154 public DataFlavor[] getAvailableDataFlavors() 155 { 156 Transferable c = getContents(null); 157 if (c == null) 158 return new DataFlavor[0]; 159 else 160 return c.getTransferDataFlavors(); 161 } 162 isDataFlavorAvailable(DataFlavor flavor)163 public boolean isDataFlavorAvailable(DataFlavor flavor) 164 { 165 DataFlavor[] fs = getAvailableDataFlavors(); 166 for (int i = 0; i < fs.length; i++) 167 if (flavor.equals(fs[i])) 168 return true; 169 170 return false; 171 } 172 getData(DataFlavor flavor)173 public Object getData(DataFlavor flavor) 174 throws UnsupportedFlavorException, IOException 175 { 176 Transferable c = getContents(null); 177 if (c == null) 178 throw new UnsupportedFlavorException(flavor); 179 else 180 return c.getTransferData(flavor); 181 } 182 addFlavorListener(FlavorListener listener)183 public void addFlavorListener(FlavorListener listener) 184 { 185 if (listener == null) 186 return; 187 188 synchronized(listeners) 189 { 190 listeners.add(listener); 191 } 192 } 193 removeFlavorListener(FlavorListener listener)194 public void removeFlavorListener(FlavorListener listener) 195 { 196 if (listener == null) 197 return; 198 199 synchronized(listeners) 200 { 201 listeners.remove(listener); 202 } 203 } 204 getFlavorListeners()205 public FlavorListener[] getFlavorListeners() 206 { 207 synchronized(listeners) 208 { 209 return (FlavorListener[]) 210 listeners.toArray(new FlavorListener[listeners.size()]); 211 } 212 } 213 } 214