1 /* AbstractAction.java -- 2 Copyright (C) 2002, 2004, 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 javax.swing; 40 41 import java.beans.PropertyChangeEvent; 42 import java.beans.PropertyChangeListener; 43 import java.io.Serializable; 44 import java.util.HashMap; 45 46 import javax.swing.event.SwingPropertyChangeSupport; 47 48 /** 49 * A base class for implementing the {@link Action} interface. 50 * 51 * @author Andrew Selkirk 52 */ 53 public abstract class AbstractAction 54 implements Action, Cloneable, Serializable 55 { 56 private static final long serialVersionUID = -6803159439231523484L; 57 58 /** 59 * A flag that indicates whether or not the action is enabled. 60 */ 61 protected boolean enabled = true; 62 63 /** 64 * Provides support for property change event notification. 65 */ 66 protected SwingPropertyChangeSupport changeSupport = 67 new SwingPropertyChangeSupport(this); 68 69 /** 70 * store 71 */ 72 private transient HashMap store = new HashMap(); 73 74 /** 75 * Creates a new action with no properties set. 76 */ AbstractAction()77 public AbstractAction() 78 { 79 // Nothing to do. 80 } 81 82 /** 83 * Creates a new action with the specified name. The name is stored as a 84 * property with the key {@link Action#NAME}, and no other properties are 85 * initialised. 86 * 87 * @param name the name (<code>null</code> permitted). 88 */ AbstractAction(String name)89 public AbstractAction(String name) 90 { 91 putValue(NAME, name); 92 } 93 94 /** 95 * Creates a new action with the specified name and icon. The name is stored 96 * as a property with the key {@link Action#NAME}, the icon is stored as a 97 * property with the key {@link Action#SMALL_ICON}, and no other properties 98 * are initialised. 99 * 100 * @param name the name (<code>null</code> permitted). 101 * @param icon the icon (<code>null</code> permitted). 102 */ AbstractAction(String name, Icon icon)103 public AbstractAction(String name, Icon icon) 104 { 105 putValue(NAME, name); 106 putValue(SMALL_ICON, icon); 107 } 108 109 /** 110 * Returns a clone of the action. 111 * 112 * @return A clone of the action. 113 * 114 * @exception CloneNotSupportedException if there is a problem cloning the 115 * action. 116 */ clone()117 protected Object clone() throws CloneNotSupportedException 118 { 119 AbstractAction copy = (AbstractAction) super.clone(); 120 copy.store = (HashMap) store.clone(); 121 return copy; 122 } 123 124 /** 125 * Returns the value associated with the specified key. 126 * 127 * @param key the key (not <code>null</code>). 128 * 129 * @return The value associated with the specified key, or 130 * <code>null</code> if the key is not found. 131 * 132 * @see #putValue(String, Object) 133 */ getValue(String key)134 public Object getValue(String key) 135 { 136 return store.get(key); 137 } 138 139 /** 140 * Sets the value associated with the specified key and sends a 141 * {@link java.beans.PropertyChangeEvent} to all registered listeners. 142 * The standard keys are: 143 * <ul> 144 * <li>{@link #NAME}</li> 145 * <li>{@link #SHORT_DESCRIPTION}</li> 146 * <li>{@link #LONG_DESCRIPTION}</li> 147 * <li>{@link #SMALL_ICON}</li> 148 * <li>{@link #ACTION_COMMAND_KEY}</li> 149 * <li>{@link #ACCELERATOR_KEY}</li> 150 * <li>{@link #MNEMONIC_KEY}</li> 151 * </ul> 152 * Any existing value associated with the key will be overwritten. 153 * 154 * @param key the key (not <code>null</code>). 155 * @param value the value (<code>null</code> permitted). 156 */ putValue(String key, Object value)157 public void putValue(String key, Object value) 158 { 159 Object old = getValue(key); 160 if ((old == null && value != null) || (old != null && !old.equals(value))) 161 { 162 store.put(key, value); 163 firePropertyChange(key, old, value); 164 } 165 } 166 167 /** 168 * Returns the flag that indicates whether or not the action is enabled. 169 * 170 * @return The flag. 171 * 172 * @see #setEnabled(boolean) 173 */ isEnabled()174 public boolean isEnabled() 175 { 176 return enabled; 177 } 178 179 /** 180 * Sets the flag that indicates whether or not the action is enabled and, if 181 * the value of the flag changed from the previous setting, sends a 182 * {@link java.beans.PropertyChangeEvent} to all registered listeners (using 183 * the property name 'enabled'). 184 * 185 * @param enabled the new flag value. 186 * 187 * @see #isEnabled() 188 */ setEnabled(boolean enabled)189 public void setEnabled(boolean enabled) 190 { 191 if (enabled != this.enabled) 192 { 193 this.enabled = enabled; 194 firePropertyChange("enabled", !this.enabled, this.enabled); 195 } 196 } 197 198 /** 199 * Returns an array of the keys for the property values that have been 200 * defined via the {@link #putValue(String, Object)} method (or the class 201 * constructor). 202 * 203 * @return An array of keys. 204 */ getKeys()205 public Object[] getKeys() 206 { 207 return store.keySet().toArray(); 208 } 209 210 /** 211 * Sends a {@link PropertyChangeEvent} for the named property to all 212 * registered listeners. 213 * 214 * @param propertyName the property name. 215 * @param oldValue the old value of the property. 216 * @param newValue the new value of the property. 217 */ firePropertyChange(String propertyName, Object oldValue, Object newValue)218 protected void firePropertyChange(String propertyName, Object oldValue, 219 Object newValue) 220 { 221 changeSupport.firePropertyChange(propertyName, oldValue, newValue); 222 } 223 224 /** 225 * Sends a {@link PropertyChangeEvent} for the named property to all 226 * registered listeners. This private method is called by the 227 * {@link #setEnabled(boolean)} method. 228 * 229 * @param propertyName the property name. 230 * @param oldValue the old value of the property. 231 * @param newValue the new value of the property. 232 */ firePropertyChange(String propertyName, boolean oldValue, boolean newValue)233 private void firePropertyChange(String propertyName, boolean oldValue, 234 boolean newValue) 235 { 236 changeSupport.firePropertyChange(propertyName, oldValue, newValue); 237 } 238 239 /** 240 * Registers a listener to receive {@link PropertyChangeEvent} notifications 241 * from this action. 242 * 243 * @param listener the listener. 244 * 245 * @see #removePropertyChangeListener(PropertyChangeListener) 246 */ addPropertyChangeListener(PropertyChangeListener listener)247 public void addPropertyChangeListener(PropertyChangeListener listener) 248 { 249 changeSupport.addPropertyChangeListener(listener); 250 } 251 252 /** 253 * Deregisters a listener so that it no longer receives 254 * {@link PropertyChangeEvent} notifications from this action. 255 * 256 * @param listener the listener. 257 * 258 * @see #addPropertyChangeListener(PropertyChangeListener) 259 */ removePropertyChangeListener(PropertyChangeListener listener)260 public void removePropertyChangeListener(PropertyChangeListener listener) 261 { 262 changeSupport.removePropertyChangeListener(listener); 263 } 264 265 /** 266 * Returns all registered listeners. 267 * 268 * @return An array of listeners. 269 * 270 * @since 1.4 271 */ getPropertyChangeListeners()272 public PropertyChangeListener[] getPropertyChangeListeners() 273 { 274 return changeSupport.getPropertyChangeListeners(); 275 } 276 } 277