001/* Action.java --
002   Copyright (C) 2002, 2004, 2005 Free Software Foundation, Inc.
003
004This file is part of GNU Classpath.
005
006GNU Classpath is free software; you can redistribute it and/or modify
007it under the terms of the GNU General Public License as published by
008the Free Software Foundation; either version 2, or (at your option)
009any later version.
010
011GNU Classpath is distributed in the hope that it will be useful, but
012WITHOUT ANY WARRANTY; without even the implied warranty of
013MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
014General Public License for more details.
015
016You should have received a copy of the GNU General Public License
017along with GNU Classpath; see the file COPYING.  If not, write to the
018Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
01902110-1301 USA.
020
021Linking this library statically or dynamically with other modules is
022making a combined work based on this library.  Thus, the terms and
023conditions of the GNU General Public License cover the whole
024combination.
025
026As a special exception, the copyright holders of this library give you
027permission to link this library with independent modules to produce an
028executable, regardless of the license terms of these independent
029modules, and to copy and distribute the resulting executable under
030terms of your choice, provided that you also meet, for each linked
031independent module, the terms and conditions of the license of that
032module.  An independent module is a module which is not derived from
033or based on this library.  If you modify this library, you may extend
034this exception to your version of the library, but you are not
035obligated to do so.  If you do not wish to do so, delete this
036exception statement from your version. */
037
038package javax.swing;
039
040import java.awt.event.ActionListener;
041import java.beans.PropertyChangeListener;
042
043/**
044 * Provides a convenient central point of control for some task
045 * that can be triggered by more than one control in a Swing user interface
046 * (for example, a menu item and a toolbar button).
047 * 
048 * @see AbstractButton#setAction(Action)
049 * 
050 * @author Ronald Veldema (rveldema@cs.vu.nl)
051 * @author Andrew Selkirk
052 */
053public interface Action extends ActionListener {
054
055  /**
056   * A key to access the default property for the action (this is not used).
057   */
058  String DEFAULT = "Default";
059
060  /**
061   * A key to access the long description for the action.
062   */
063  String LONG_DESCRIPTION = "LongDescription";
064
065  /**
066   * A key to access the name for the action.
067   */
068  String NAME = "Name";
069
070  /**
071   * A key to access the short description for the action (the short
072   * description is typically used as the tool tip text).
073   */
074  String SHORT_DESCRIPTION = "ShortDescription";
075
076  /**
077   * A key to access the icon for the action.
078   */
079  String SMALL_ICON = "SmallIcon";
080
081  /**
082   * A key to access the {@link KeyStroke} used as the accelerator for the
083   * action.
084   */
085  String ACCELERATOR_KEY = "AcceleratorKey";
086
087  /**
088   * A key to access the action command string for the action.
089   */
090  String ACTION_COMMAND_KEY = "ActionCommandKey";
091
092  /**
093   * A key to access the mnemonic for the action.
094   */
095  String MNEMONIC_KEY = "MnemonicKey";
096
097  /**
098   * Returns the value associated with the specified key.
099   * 
100   * @param key  the key (not <code>null</code>).
101   * 
102   * @return The value associated with the specified key, or 
103   *         <code>null</code> if the key is not found.
104   */
105  Object getValue(String key);
106
107  /**
108   * Sets the value associated with the specified key and sends a 
109   * {@link java.beans.PropertyChangeEvent} to all registered listeners.  
110   * The standard keys are defined in this interface: {@link #NAME}, 
111   * {@link #SHORT_DESCRIPTION}, {@link #LONG_DESCRIPTION}, 
112   * {@link #SMALL_ICON}, {@link #ACTION_COMMAND_KEY}, 
113   * {@link #ACCELERATOR_KEY} and {@link #MNEMONIC_KEY}. Any existing value 
114   * associated with the key will be overwritten.  
115   * 
116   * @param key  the key (not <code>null</code>).
117   * @param value  the value (<code>null</code> permitted).
118   */
119  void putValue(String key, Object value);
120
121  /**
122   * Returns the flag that indicates whether or not this action is enabled.
123   * 
124   * @return The flag.
125   */
126  boolean isEnabled();
127
128  /**
129   * Sets the flag that indicates whether or not this action is enabled.  If
130   * the value changes, a {@link java.beans.PropertyChangeEvent} is sent to 
131   * all registered listeners.
132   * 
133   * @param b  the new value of the flag.
134   */
135  void setEnabled(boolean b);
136
137  /**
138   * Registers a listener to receive notification whenever one of the
139   * action's properties is modified.
140   * 
141   * @param listener  the listener.
142   */
143  void addPropertyChangeListener(PropertyChangeListener listener);
144
145  /**
146   * Deregisters a listener so that it no longer receives notification of
147   * changes to the action's properties. 
148   * 
149   * @param listener  the listener.
150   */
151  void removePropertyChangeListener(PropertyChangeListener listener);
152
153} // Action