libjava/classpath/javax/swing/InputMap.java

   1 /* InputMap.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., 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 package javax.swing;
  39
  40 import java.io.IOException;
  41 import java.io.ObjectInputStream;
  42 import java.io.ObjectOutputStream;
  43 import java.io.Serializable;
  44 import java.util.Arrays;
  45 import java.util.HashMap;
  46 import java.util.HashSet;
  47 import java.util.Map;
  48 import java.util.Set;
  49
  50
  51 /**
  52  * Maps {@link KeyStroke}s to arbitrary objects, usually Strings. This
  53  * is used in combination with {@link ActionMap}s.
  54  *
  55  * If a component receives an input event, this is looked up in
  56  * the component's <code>InputMap</code>. The result is an object which
  57  * serves as a key to the components <code>ActionMap</code>. Finally
  58  * the <code>Action</code> that is stored is executed.
  59  *
  60  * @author Andrew Selkirk
  61  * @author Michael Koch
  62  *
  63  * @since 1.3
  64  */
  65 public class InputMap
  66   implements Serializable
  67 {
  68   private static final long serialVersionUID = -5429059542008604257L;
  69
  70   /**
  71    * inputMap
  72    */
  73   private Map inputMap = new HashMap();
  74
  75   /**
  76    * parent
  77    */
  78   private InputMap parent;
  79
  80   /**
  81    * Creates a new <code>InputMap</code> instance.
  82    */
  83   public InputMap()
  84   {
  85     // TODO
  86   }
  87
  88   /**
  89    * Returns the binding for keystroke.
  90    *
  91    * @param keystroke the key of the enty
  92    *
  93    * @return the binding associated with keystroke may be null
  94    */
  95   public Object get(KeyStroke keystroke)
  96   {
  97     Object result = inputMap.get(keystroke);
  98
  99     if (result == null && parent != null)
 100       result = parent.get(keystroke);
 101     return result;
 102   }
 103
 104   /**
 105    * Puts a new entry into the <code>InputMap</code>.
 106    * If actionMapKey is null an existing entry will be removed.
 107    *
 108    * @param keystroke the keystroke for the entry
 109    * @param actionMapKey the action.
 110    */
 111   public void put(KeyStroke keystroke, Object actionMapKey)
 112   {
 113     if (actionMapKey == null)
 114       inputMap.remove(keystroke);
 115     else
 116       inputMap.put(keystroke, actionMapKey);
 117   }
 118
 119   /**
 120    * Remove an entry from the <code>InputMap</code>.
 121    *
 122    * @param keystroke the key of the entry to remove
 123    */
 124   public void remove(KeyStroke keystroke)
 125   {
 126     inputMap.remove(keystroke);
 127   }
 128
 129   /**
 130    * Returns the parent of this <code>InputMap</code>.
 131    *
 132    * @return the parent, may be null.
 133    */
 134   public InputMap getParent()
 135   {
 136     return parent;
 137   }
 138
 139   /**
 140    * Sets a parent for this <code>InputMap</code>.
 141    *
 142    * @param parentMap the new parent
 143    */
 144   public void setParent(InputMap parentMap)
 145   {
 146     parent = parentMap;
 147   }
 148
 149   /**
 150    * Returns the number of entries in this <code>InputMap</code>.
 151    *
 152    * @return the number of entries
 153    */
 154   public int size()
 155   {
 156     return inputMap.size();
 157   }
 158
 159   /**
 160    * Clears the <code>InputMap</code>.
 161    */
 162   public void clear()
 163   {
 164     inputMap.clear();
 165   }
 166
 167   /**
 168    * Returns all keys of entries in this <code>InputMap</code>.
 169    *
 170    * @return an array of keys
 171    */
 172   public KeyStroke[] keys()
 173   {
 174     if (size() != 0)
 175       {
 176         KeyStroke[] array = new KeyStroke[size()];
 177         return (KeyStroke[]) inputMap.keySet().toArray(array);
 178       }
 179     return null;
 180   }
 181
 182   /**
 183    * Returns all keys of entries in this <code>InputMap</code>
 184    * and all its parents.
 185    *
 186    * @return an array of keys
 187    */
 188   public KeyStroke[] allKeys()
 189   {
 190     Set set = new HashSet();
 191
 192     if (parent != null)
 193       set.addAll(Arrays.asList(parent.allKeys()));
 194
 195     set.addAll(inputMap.keySet());
 196     if (set.size() == 0)
 197       return null;
 198     KeyStroke[] array = new KeyStroke[set.size()];
 199     return (KeyStroke[]) set.toArray(array);
 200   }
 201
 202   /**
 203    * writeObject
 204    *
 205    * @param stream the stream to write to
 206    *
 207    * @exception IOException If an error occurs
 208    */
 209   private void writeObject(ObjectOutputStream stream) throws IOException
 210   {
 211     // TODO
 212   }
 213
 214   /**
 215    * readObject
 216    *
 217    * @param stream the stream to read from
 218    *
 219    * @exception ClassNotFoundException If the serialized class cannot be found
 220    * @exception IOException If an error occurs
 221    */
 222   private void readObject(ObjectInputStream stream)
 223     throws ClassNotFoundException, IOException
 224   {
 225     // TODO
 226   }
 227 }