old-autovect-branch/libjava/classpath/javax/swing/AbstractCellEditor.java

   1 /* AbstractCellEditor.java --
   2    Copyright (C) 2002, 2004, 2005 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.io.Serializable;
  42 import java.util.EventObject;
  43
  44 import javax.swing.event.CellEditorListener;
  45 import javax.swing.event.ChangeEvent;
  46 import javax.swing.event.EventListenerList;
  47
  48 /**
  49  * An abstract superclass for table and tree cell editors. This provides some
  50  * common shared functionality.
  51  *
  52  * @author Andrew Selkirk
  53  */
  54 public abstract class AbstractCellEditor
  55   implements CellEditor, Serializable
  56 {
  57   private static final long serialVersionUID = -1048006551406220959L;
  58
  59   /**
  60    * Our Swing event listeners.
  61    */
  62   protected EventListenerList listenerList;
  63
  64   /**
  65    * The cached ChangeEvent.
  66    */
  67   protected transient ChangeEvent changeEvent;
  68
  69   /**
  70    * Creates a new instance of AbstractCellEditor.
  71    */
  72   public AbstractCellEditor() {
  73     listenerList = new EventListenerList();
  74     changeEvent = new ChangeEvent(this);
  75   } // AbstractCellEditor()
  76
  77   /**
  78    * Returns <code>true</code> if the cell is editable using
  79    * <code>event</code>, <code>false</code>
  80    * if it's not. The default behaviour is to return <code>true</code>.
  81    *
  82    * @param event an event
  83    *
  84    * @return <code>true</code> if the cell is editable using
  85    *     <code>event</code>, <code>false</code> if it's not
  86    */
  87   public boolean isCellEditable(EventObject event) {
  88     return true;
  89   } // isCellEditable()
  90
  91   /**
  92    * Returns <code>true</code> if the editing cell should be selected,
  93    * <code>false</code> otherwise. This is usually returning <code>true</code>,
  94    * but in some special cases it might be useful not to switch cell selection
  95    * when editing one cell.
  96    *
  97    * @param event an event
  98    *
  99    * @return <code>true</code> if the editing cell should be selected,
 100    *     <code>false</code> otherwise
 101    */
 102   public boolean shouldSelectCell(EventObject event) {
 103     return true;
 104   } // shouldSelectCell()
 105
 106   /**
 107    * Stop editing the cell and accept any partial value that has been entered
 108    * into the cell.
 109    *
 110    * @returns <code>true</code> if editing has been stopped successfully,
 111    *     <code>false</code>otherwise
 112    */
 113   public boolean stopCellEditing() {
 114     fireEditingStopped();
 115     return true;
 116   } // stopCellEditing()
 117
 118   /**
 119    * Stop editing the cell and do not accept any partial value that has
 120    * been entered into the cell.
 121    */
 122   public void cancelCellEditing() {
 123     fireEditingCanceled();
 124   } // cancelCellEditing()
 125
 126   /**
 127    * Adds a CellEditorListener to the list of CellEditorListeners of this
 128    * CellEditor.
 129    *
 130    * @param listener the CellEditorListener to add
 131    */
 132   public void addCellEditorListener (CellEditorListener listener)
 133   {
 134     listenerList.add (CellEditorListener.class, listener);
 135   }
 136
 137   /**
 138    * Removes the specified CellEditorListener from the list of the
 139    * CellEditorListeners of this CellEditor.
 140    *
 141    * @param listener the CellEditorListener to remove
 142    */
 143   public void removeCellEditorListener (CellEditorListener listener)
 144   {
 145     listenerList.remove (CellEditorListener.class, listener);
 146   }
 147
 148   /**
 149    * Returns the list of CellEditorListeners that have been registered
 150    * in this CellEditor.
 151    *
 152    * @return the list of CellEditorListeners that have been registered
 153    *     in this CellEditor
 154    *
 155    * @since 1.4
 156    */
 157   public CellEditorListener[] getCellEditorListeners()
 158   {
 159     return (CellEditorListener[]) listenerList.getListeners
 160       (CellEditorListener.class);
 161   }
 162
 163   /**
 164    * Notifies all registered listeners that the editing of the cell has has been
 165    * stopped.
 166    */
 167   protected void fireEditingStopped()
 168   {
 169     CellEditorListener[] listeners = getCellEditorListeners();
 170
 171     for (int index = 0; index < listeners.length; index++)
 172       {
 173         listeners[index].editingStopped(changeEvent);
 174       }
 175   }
 176
 177   /**
 178    * Notifies all registered listeners that the editing of the cell has
 179    * has been canceled.
 180    */
 181   protected void fireEditingCanceled()
 182   {
 183     CellEditorListener[] listeners = getCellEditorListeners();
 184
 185     for (int index = 0; index < listeners.length; index++)
 186       {
 187         listeners[index].editingCanceled(changeEvent);
 188       }
 189   }
 190 }