gomp-20050608-branch/libjava/classpath/javax/swing/AbstractAction.java

   1 /* AbstractAction.java --
   2    Copyright (C) 2002, 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.beans.PropertyChangeListener;
  42 import java.io.IOException;
  43 import java.io.ObjectInputStream;
  44 import java.io.ObjectOutputStream;
  45 import java.io.Serializable;
  46 import java.util.HashMap;
  47
  48 import javax.swing.event.SwingPropertyChangeSupport;
  49
  50 /**
  51  * A base class for implementing the {@link Action} interface.
  52  *
  53  * @author Andrew Selkirk
  54  */
  55 public abstract class AbstractAction
  56   implements Action, Cloneable, Serializable
  57 {
  58   private static final long serialVersionUID = -6803159439231523484L;
  59
  60   /**
  61    * A flag that indicates whether or not the action is enabled.
  62    */
  63   protected boolean enabled = true;
  64
  65   /**
  66    * Provides support for property change event notification.
  67    */
  68   protected SwingPropertyChangeSupport changeSupport =
  69     new SwingPropertyChangeSupport(this);
  70
  71   /**
  72    * store
  73    */
  74   private transient HashMap store = new HashMap();
  75
  76   /**
  77    * Creates a new action with an empty string for the name.  All other
  78    * properties are initialised to <code>null</code>
  79    */
  80   public AbstractAction()
  81   {
  82     this(null);
  83   }
  84
  85   /**
  86    * Creates a new action with the specified name.  All other properties are
  87    * initialised to <code>null</code>.
  88    *
  89    * @param name  the name (<code>null</code> permitted).
  90    */
  91   public AbstractAction(String name)
  92   {
  93     this(name, null);
  94   }
  95
  96   /**
  97    * Creates a new action with the specified name and icon.  All other
  98    * properties are initialised to <code>null</code>.
  99    *
 100    * @param name  the name (<code>null</code> permitted).
 101    * @param icon  the icon (<code>null</code> permitted).
 102    */
 103   public AbstractAction(String name, Icon icon)
 104   {
 105     putValue(NAME, name);
 106     putValue(SMALL_ICON, icon);
 107   }
 108
 109   /**
 110    * readObject
 111    *
 112    * @param stream the stream to read from
 113    *
 114    * @exception ClassNotFoundException TODO
 115    * @exception IOException if an error occurs
 116    */
 117   private void readObject(ObjectInputStream stream)
 118     throws ClassNotFoundException, IOException
 119   {
 120     // TODO
 121   }
 122
 123   /**
 124    * writeObject
 125    *
 126    * @param stream the stream to write to
 127    *
 128    * @exception IOException if an error occurs
 129    */
 130   private void writeObject(ObjectOutputStream stream) throws IOException
 131   {
 132     // TODO
 133   }
 134
 135   /**
 136    * clone
 137    *
 138    * @return Object
 139    *
 140    * @exception CloneNotSupportedException TODO
 141    */
 142   protected Object clone() throws CloneNotSupportedException
 143   {
 144     AbstractAction copy = (AbstractAction) super.clone();
 145     copy.store = (HashMap) store.clone();
 146     return copy;
 147   }
 148
 149   /**
 150    * Returns the value associated with the specified key.
 151    *
 152    * @param key  the key (not <code>null</code>).
 153    *
 154    * @return The value associated with the specified key, or
 155    *         <code>null</code> if the key is not found.
 156    */
 157   public Object getValue(String key)
 158   {
 159     return store.get(key);
 160   }
 161
 162   /**
 163    * Sets the value associated with the specified key and sends a
 164    * {@link java.beans.PropertyChangeEvent} to all registered listeners.
 165    * The standard keys are: {@link #NAME}, {@link #SHORT_DESCRIPTION},
 166    * {@link #LONG_DESCRIPTION}, {@link #SMALL_ICON},
 167    * {@link #ACTION_COMMAND_KEY}, {@link #ACCELERATOR_KEY} and
 168    * {@link #MNEMONIC_KEY}. Any existing value associated with the key will be
 169    * overwritten.
 170    *
 171    * @param key  the key (not <code>null</code>).
 172    * @param value  the value (<code>null</code> permitted).
 173    */
 174   public void putValue(String key, Object value)
 175   {
 176     Object old = getValue(key);
 177     if (old == null || !old.equals(value))
 178     {
 179       store.put(key, value);
 180       firePropertyChange(key, old, value);
 181     }
 182   }
 183
 184   /**
 185    * Returns the flag that indicates whether or not the action is enabled.
 186    *
 187    * @return The flag.
 188    */
 189   public boolean isEnabled()
 190   {
 191     return enabled;
 192   }
 193
 194   /**
 195    * Sets the flag that indicates whether or not the action is enabled and, if
 196    * the value of the flag changed from the previous setting, sends a
 197    * {@link java.beans.PropertyChangeEvent} to all registered listeners.
 198    *
 199    * @param enabled  the new flag value.
 200    */
 201   public void setEnabled(boolean enabled)
 202   {
 203     if (enabled != this.enabled)
 204     {
 205       this.enabled = enabled;
 206       firePropertyChange("enabled", !this.enabled, this.enabled);
 207     }
 208   }
 209
 210   /**
 211    * getKeys
 212    * @returns Object[]
 213    */
 214   public Object[] getKeys()
 215   {
 216     return store.keySet().toArray();
 217   }
 218
 219   /**
 220    * This method fires a PropertyChangeEvent given the propertyName
 221    * and the old and new values.
 222    *
 223    * @param propertyName The property that changed.
 224    * @param oldValue The old value of the property.
 225    * @param newValue The new value of the property.
 226    */
 227   protected void firePropertyChange(String propertyName, Object oldValue,
 228                                     Object newValue)
 229   {
 230     changeSupport.firePropertyChange(propertyName, oldValue, newValue);
 231   }
 232
 233   /**
 234    * This convenience method fires a PropertyChangeEvent given
 235    * the propertyName and the old and new values.
 236    *
 237    * @param propertyName The property that changed.
 238    * @param oldValue The old value of the property.
 239    * @param newValue The new value of the property.
 240    */
 241   private void firePropertyChange(String propertyName, boolean oldValue, boolean newValue)
 242   {
 243     changeSupport.firePropertyChange(propertyName, oldValue, newValue);
 244   }
 245
 246   /**
 247    * addPropertyChangeListener
 248    *
 249    * @param listener the listener to add
 250    */
 251   public void addPropertyChangeListener(PropertyChangeListener listener)
 252   {
 253     changeSupport.addPropertyChangeListener(listener);
 254   }
 255
 256   /**
 257    * removePropertyChangeListener
 258    *
 259    * @param listener the listener to remove
 260    */
 261   public void removePropertyChangeListener(PropertyChangeListener listener)
 262   {
 263     changeSupport.removePropertyChangeListener(listener);
 264   }
 265
 266   /**
 267    * Returns all registered listeners.
 268    *
 269    * @return array of listeners.
 270    *
 271    * @since 1.4
 272    */
 273   public PropertyChangeListener[] getPropertyChangeListeners()
 274   {
 275     return changeSupport.getPropertyChangeListeners();
 276   }
 277 }