001    /* CheckboxGroup.java -- A grouping class for checkboxes.
002       Copyright (C) 1999, 2000, 2002, 2005  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 java.awt;
040    
041    /**
042      * This class if for combining checkboxes into groups so that only
043      * one checkbox in the group can be selected at any one time.
044      *
045      * @author Aaron M. Renn (arenn@urbanophile.com)
046      * @author Tom Tromey (tromey@redhat.com)
047      */
048    public class CheckboxGroup implements java.io.Serializable
049    {
050    
051    /*
052     * Static Variables
053     */
054    
055    // Serialization constant
056    private static final long serialVersionUID = 3729780091441768983L;
057    
058    /*************************************************************************/
059    
060    /*
061     * Instance Variables
062     */
063    
064    /**
065      * @serial The currently selected checkbox.
066      */
067    private Checkbox selectedCheckbox;
068    
069    /*************************************************************************/
070    
071    /*
072     * Constructors
073     */
074    
075    /**
076      * Initializes a new instance of <code>CheckboxGroup</code>.
077      */
078    public
079    CheckboxGroup()
080    {
081    }
082    
083    /*************************************************************************/
084    
085    /*
086     * Instance Methods
087     */
088    
089    /**
090      * Returns the currently selected checkbox, or <code>null</code> if none
091      * of the checkboxes in this group are selected.
092      *
093      * @return The selected checkbox.
094      */
095    public Checkbox
096    getSelectedCheckbox()
097    {
098      return getCurrent ();
099    }
100    
101    /*************************************************************************/
102    
103    /**
104      * Returns the currently selected checkbox, or <code>null</code> if none
105      * of the checkboxes in this group are selected.
106      *
107      * @return The selected checkbox.
108      *
109      * @deprecated This method is deprecated in favor of 
110      * <code>getSelectedCheckbox()</code>.
111      */
112    public Checkbox
113    getCurrent()
114    {
115      return(selectedCheckbox);
116    } 
117    
118    /*************************************************************************/
119    
120    /**
121      * This method sets the specified checkbox to be the selected on in this
122      * group, and unsets all others.
123      *
124      * @param selectedCheckbox The new selected checkbox.
125      */
126    public void
127    setSelectedCheckbox(Checkbox selectedCheckbox)
128    {
129      setCurrent (selectedCheckbox);
130    }
131    
132    /*************************************************************************/
133    
134    /**
135      * This method sets the specified checkbox to be the selected on in this
136      * group, and unsets all others.
137      *
138      * @param selectedCheckbox The new selected checkbox.
139      *
140      * @deprecated This method is deprecated in favor of
141      * <code>setSelectedCheckbox()</code>.
142      */
143    public void
144    setCurrent(Checkbox selectedCheckbox)
145    {
146      if (this.selectedCheckbox != null)
147        {
148          if (this.selectedCheckbox.getCheckboxGroup() != this)
149            return;
150    
151          this.selectedCheckbox.setState(false);
152        }
153    
154      this.selectedCheckbox = selectedCheckbox;
155      if (selectedCheckbox != null)
156        selectedCheckbox.setState(true);
157    }
158    
159    /*************************************************************************/
160    
161    /**
162      * Returns a string representation of this checkbox group.
163      *
164      * @return A string representation of this checkbox group.
165      */
166    public String
167    toString()
168    {
169      return(getClass().getName() + "[selectedCheckbox=" + selectedCheckbox + "]");
170    }
171    
172    } // class CheckboxGroup 
173