libjava/javax/swing/event/SwingPropertyChangeSupport.java

   1 /* SwingPropertyChangeSupport.java --
   2    Copyright (C) 2002 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 package javax.swing.event;
  39
  40 // Imports
  41 import java.beans.*;
  42 import java.io.*;
  43 import java.util.*;
  44
  45 /**
  46  * SwingPropertyChangeSupport
  47  * @author Andrew Selkirk
  48 */
  49 public final    class SwingPropertyChangeSupport
  50                                 extends PropertyChangeSupport {
  51
  52   private static final long serialVersionUID = 7162625831330845068L;
  53
  54         //-------------------------------------------------------------
  55         // Variables --------------------------------------------------
  56         //-------------------------------------------------------------
  57
  58         /**
  59          * listeners
  60          */
  61         private transient EventListenerList listeners;
  62
  63         /**
  64          * propertyListeners
  65          */
  66         private Hashtable propertyListeners;
  67
  68         /**
  69          * source
  70          */
  71         private Object source;
  72
  73
  74         //-------------------------------------------------------------
  75         // Initialization ---------------------------------------------
  76         //-------------------------------------------------------------
  77
  78         /**
  79          * Constructor SwingPropertyChangeSupport
  80          * @param source TODO
  81          */
  82         public SwingPropertyChangeSupport(Object source) {
  83                 super(source);
  84                 this.source = source;
  85                 this.listeners = new EventListenerList();
  86                 this.propertyListeners = new Hashtable();
  87         } // SwingPropertyChangeSupport()
  88
  89
  90         //-------------------------------------------------------------
  91         // Methods ----------------------------------------------------
  92         //-------------------------------------------------------------
  93
  94         /**
  95          * writeObject
  96          * @param stream TODO
  97          * @exception IOException TODO
  98          */
  99         private void writeObject(ObjectOutputStream stream) throws IOException {
 100                 // TODO
 101         } // writeObject()
 102
 103         /**
 104          * readObject
 105          * @param stream TODO
 106          * @exception ClassNotFoundException TODO
 107          * @exception IOException TODO
 108          */
 109         private void readObject(ObjectInputStream stream) throws ClassNotFoundException, IOException {
 110                 // TODO
 111         } // readObject()
 112
 113         /**
 114          * addPropertyChangeListener
 115          * @param listener TODO
 116          */
 117         public synchronized void addPropertyChangeListener(PropertyChangeListener listener) {
 118                 listeners.add(PropertyChangeListener.class, listener);
 119         } // addPropertyChangeListener()
 120
 121         /**
 122          * addPropertyChangeListener
 123          * @param propertyName TODO
 124          * @param listener TODO
 125          */
 126         public synchronized void addPropertyChangeListener(String propertyName, PropertyChangeListener listener) {
 127
 128                 // Variables
 129                 EventListenerList       list;
 130
 131                 // Get Listener list
 132                 list = (EventListenerList) propertyListeners.get(propertyName);
 133                 if (list == null) {
 134                         list = new EventListenerList();
 135                         propertyListeners.put(propertyName, list);
 136                 } // if
 137
 138                 // Add Listeners
 139                 list.add(PropertyChangeListener.class, listener);
 140
 141         } // addPropertyChangeListener()
 142
 143         /**
 144          * removePropertyChangeListener
 145          * @param listener TODO
 146          */
 147         public synchronized void removePropertyChangeListener(PropertyChangeListener listener) {
 148                 listeners.remove(PropertyChangeListener.class, listener);
 149         } // removePropertyChangeListener()
 150
 151         /**
 152          * removePropertyChangeListener
 153          * @param propertyName TODO
 154          * @param listener TODO
 155          */
 156         public synchronized void removePropertyChangeListener(String propertyName, PropertyChangeListener listener) {
 157
 158                 // Variables
 159                 EventListenerList       list;
 160
 161                 // Get Listener list
 162                 list = (EventListenerList) propertyListeners.get(propertyName);
 163                 if (list == null) {
 164                         return;
 165                 } // if
 166
 167                 // Remove Listeners
 168                 list.remove(PropertyChangeListener.class, listener);
 169
 170                 // Clean up propertyListeners
 171                 if (list.getListenerCount() == 0) {
 172                         propertyListeners.remove(propertyName);
 173                 } // if
 174
 175         } // removePropertyChangeListener()
 176
 177         /**
 178          * firePropertyChange
 179          * @param propertyName TODO
 180          * @param oldValue TODO
 181          * @param newValue TODO
 182          */
 183         public void firePropertyChange(String propertyName, Object oldValue, Object newValue) {
 184
 185                 // Variables
 186                 PropertyChangeEvent     event;
 187
 188                 // Create Property Change Event
 189                 event = new PropertyChangeEvent(source, propertyName, oldValue, newValue);
 190
 191                 // Fire Event
 192                 firePropertyChange(event);
 193
 194         } // firePropertyChange()
 195
 196         /**
 197          * firePropertyChange
 198          * @param event TODO
 199          */
 200         public void firePropertyChange(PropertyChangeEvent event) {
 201
 202                 // Variables
 203                 EventListenerList               list;
 204                 EventListener[]                 listenerList;
 205                 int                                             index;
 206                 PropertyChangeListener  listener;
 207
 208                 // Check Values if they are equal
 209                 if (event.getOldValue() == null || event.getNewValue() == null ||
 210                         event.getOldValue().equals(event.getNewValue()) == true) {
 211                         return;
 212                 } // if
 213
 214                 // Process Main Listener List
 215                 listenerList = listeners.getListeners(PropertyChangeListener.class);
 216                 for (index = 0; index < listenerList.length; index++) {
 217                         listener = (PropertyChangeListener) listenerList[index];
 218                         listener.propertyChange(event);
 219                 } // for
 220
 221                 // Process Property Listener List
 222                 list = (EventListenerList) propertyListeners.get(event.getPropertyName());
 223                 if (list != null) {
 224                         listenerList = list.getListeners(PropertyChangeListener.class);
 225                         for (index = 0; index < listenerList.length; index++) {
 226                                 listener = (PropertyChangeListener) listenerList[index];
 227                                 listener.propertyChange(event);
 228                         } // for
 229                 } // if
 230
 231         } // firePropertyChange()
 232
 233         /**
 234          * hasListeners
 235          * @param propertyName TODO
 236          * @returns boolean
 237          */
 238         public synchronized boolean hasListeners(String propertyName) {
 239
 240                 // Get Listener list
 241                 if (propertyListeners.get(propertyName) == null) {
 242                         return false;
 243                 } // if
 244
 245                 return true;
 246
 247         } // hasListeners()
 248
 249
 250 } // SwingPropertyChangeSupport