001    /* DefaultColorSelectionModel.java --
002       Copyright (C) 2002, 2004  Free Software Foundation, Inc.
003    
004    This file is part of GNU Classpath.
005    
006    GNU Classpath is free software; you can redistribute it and/or modify
007    it under the terms of the GNU General Public License as published by
008    the Free Software Foundation; either version 2, or (at your option)
009    any later version.
010    
011    GNU Classpath is distributed in the hope that it will be useful, but
012    WITHOUT ANY WARRANTY; without even the implied warranty of
013    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
014    General Public License for more details.
015    
016    You should have received a copy of the GNU General Public License
017    along with GNU Classpath; see the file COPYING.  If not, write to the
018    Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
019    02110-1301 USA.
020    
021    Linking this library statically or dynamically with other modules is
022    making a combined work based on this library.  Thus, the terms and
023    conditions of the GNU General Public License cover the whole
024    combination.
025    
026    As a special exception, the copyright holders of this library give you
027    permission to link this library with independent modules to produce an
028    executable, regardless of the license terms of these independent
029    modules, and to copy and distribute the resulting executable under
030    terms of your choice, provided that you also meet, for each linked
031    independent module, the terms and conditions of the license of that
032    module.  An independent module is a module which is not derived from
033    or based on this library.  If you modify this library, you may extend
034    this exception to your version of the library, but you are not
035    obligated to do so.  If you do not wish to do so, delete this
036    exception statement from your version. */
037    
038    
039    package javax.swing.colorchooser;
040    
041    import java.awt.Color;
042    import java.io.Serializable;
043    
044    import javax.swing.event.ChangeEvent;
045    import javax.swing.event.ChangeListener;
046    import javax.swing.event.EventListenerList;
047    
048    /**
049     * This is the default implementation of the ColorSelectionModel interface
050     * that JColorChoosers use.
051     *
052     * @author Andrew Selkirk
053     * @version 1.0
054     */
055    public class DefaultColorSelectionModel implements ColorSelectionModel,
056                                                       Serializable
057    {
058      /** DOCUMENT ME! */
059      private static final long serialVersionUID = -8117143602864778804L;
060    
061      /** The currently selected color. */
062      private Color selectedColor;
063    
064      /** The ChangeEvent fired to all ChangeListeners. */
065      protected transient ChangeEvent changeEvent = new ChangeEvent(this);
066    
067      /** The list of listeners. */
068      protected EventListenerList listenerList = new EventListenerList();
069    
070      /**
071       * Creates a new color selection model with the default white color.
072       */
073      public DefaultColorSelectionModel()
074      {
075        this(Color.white);
076      }
077    
078      /**
079       * Creates a new color selection model with a given selected color.
080       *
081       * @param color The initial color.
082       *
083       * @throws Error If the color is null.
084       */
085      public DefaultColorSelectionModel(Color color)
086      {
087        super();
088        if (color == null)
089          throw new Error("ColorSelectionModel cannot be set to have null color.");
090        this.selectedColor = color;
091      }
092    
093      /**
094       * Returns the selected color.
095       *
096       * @return The selected color.
097       */
098      public Color getSelectedColor()
099      {
100        return selectedColor;
101      }
102    
103      /**
104       * This method sets the color.
105       *
106       * @param color The color to set.
107       *
108       * @throws Error If the color is set.
109       */
110      public void setSelectedColor(Color color)
111      {
112        if (color == null)
113          throw new Error("ColorSelectionModel cannot be set to have null color.");
114        if (color != selectedColor)
115          {
116            this.selectedColor = color;
117            fireStateChanged();
118          }
119      }
120    
121      /**
122       * Adds a listener to this model.
123       *
124       * @param listener The listener to add.
125       */
126      public void addChangeListener(ChangeListener listener)
127      {
128        listenerList.add(ChangeListener.class, listener);
129      }
130    
131      /**
132       * Removes a listener from this model.
133       *
134       * @param listener The listener to remove.
135       */
136      public void removeChangeListener(ChangeListener listener)
137      {
138        listenerList.remove(ChangeListener.class, listener);
139      }
140    
141      /**
142       * Returns all currently added <code>ChangeListener</code> objects.
143       *
144       * @return Array of <code>ChangeListener</code> objects.
145       */
146      public ChangeListener[] getChangeListeners()
147      {
148        return (ChangeListener[]) listenerList.getListeners(ChangeListener.class);
149      }
150    
151      /**
152       * Calls all the <code>stateChanged()</code> method of all added
153       * <code>ChangeListener</code> objects with <code>changeEvent</code> as
154       * argument.
155       */
156      protected void fireStateChanged()
157      {
158        ChangeListener[] listeners = getChangeListeners();
159    
160        for (int i = 0; i < listeners.length; i++)
161          listeners[i].stateChanged(changeEvent);
162      }
163    }