libjava/javax/swing/colorchooser/DefaultColorSelectionModel.java

   1 /* DefaultColorSelectionModel.java --
   2    Copyright (C) 2002, 2004  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
  39 package javax.swing.colorchooser;
  40
  41 import java.awt.Color;
  42 import java.io.Serializable;
  43
  44 import javax.swing.event.ChangeEvent;
  45 import javax.swing.event.ChangeListener;
  46 import javax.swing.event.EventListenerList;
  47
  48 /**
  49  * This is the default implementation of the ColorSelectionModel interface
  50  * that JColorChoosers use.
  51  *
  52  * @author Andrew Selkirk
  53  * @version 1.0
  54  */
  55 public class DefaultColorSelectionModel implements ColorSelectionModel,
  56                                                    Serializable
  57 {
  58   /** DOCUMENT ME! */
  59   private static final long serialVersionUID = -8117143602864778804L;
  60
  61   /** The currently selected color. */
  62   private Color selectedColor;
  63
  64   /** The ChangeEvent fired to all ChangeListeners. */
  65   protected transient ChangeEvent changeEvent = new ChangeEvent(this);
  66
  67   /** The list of listeners. */
  68   protected EventListenerList listenerList = new EventListenerList();
  69
  70   /**
  71    * Creates a new color selection model with the default white color.
  72    */
  73   public DefaultColorSelectionModel()
  74   {
  75     this(Color.white);
  76   }
  77
  78   /**
  79    * Creates a new color selection model with a given selected color.
  80    *
  81    * @param color The initial color.
  82    *
  83    * @throws Error If the color is null.
  84    */
  85   public DefaultColorSelectionModel(Color color)
  86   {
  87     super();
  88     if (color == null)
  89       throw new Error("ColorSelectionModel cannot be set to have null color.");
  90     this.selectedColor = color;
  91   }
  92
  93   /**
  94    * Returns the selected color.
  95    *
  96    * @return The selected color.
  97    */
  98   public Color getSelectedColor()
  99   {
 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 }