libjava/javax/accessibility/AccessibleRelation.java

   1 /* AccessibleRelation.java -- the relation between accessible objects
   2    Copyright (C) 2002 Free Software Foundation
   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 package javax.accessibility;
  39
  40 /**
  41  * The relation between one accessible object and one or more other objects.
  42  * For example, a button may control an action. An AccessibleRelationSet
  43  * summarizes all relations of the object. This strongly typed "enumeration"
  44  * supports localized strings. If the constants of this class are not
  45  * adequate, new ones may be added in a similar matter.
  46  *
  47  * @author Eric Blake (ebb9@email.byu.edu)
  48  * @since 1.2
  49  * @status updated to 1.4
  50  */
  51 public class AccessibleRelation extends AccessibleBundle
  52 {
  53   /**
  54    * Indicates the object labels other objects.
  55    *
  56    * @see #getTarget()
  57    * @see #CONTROLLER_FOR
  58    * @see #CONTROLLED_BY
  59    * @see #LABELED_BY
  60    * @see #MEMBER_OF
  61    */
  62   public static final String LABEL_FOR = "labelFor";
  63
  64   /**
  65    * Indicates the object is labeled by other objects.
  66    *
  67    * @see #getTarget()
  68    * @see #CONTROLLER_FOR
  69    * @see #CONTROLLED_BY
  70    * @see #LABEL_FOR
  71    * @see #MEMBER_OF
  72    */
  73   public static final String LABELED_BY = "labeledBy";
  74
  75   /**
  76    * Indicates an object is a member of a group of target objects.
  77    *
  78    * @see #getTarget()
  79    * @see #CONTROLLER_FOR
  80    * @see #CONTROLLED_BY
  81    * @see #LABEL_FOR
  82    * @see #LABELED_BY
  83    */
  84   public static final String MEMBER_OF = "memberOf";
  85
  86   /**
  87    * Indicates an object is a controller for other objects.
  88    *
  89    * @see #getTarget()
  90    * @see #CONTROLLED_BY
  91    * @see #LABEL_FOR
  92    * @see #LABELED_BY
  93    * @see #MEMBER_OF
  94    */
  95   public static final String CONTROLLER_FOR = "controllerFor";
  96
  97   /**
  98    * Indicates an object is controlled by other objects.
  99    *
 100    * @see #getTarget()
 101    * @see #CONTROLLER_FOR
 102    * @see #LABEL_FOR
 103    * @see #LABELED_BY
 104    * @see #MEMBER_OF
 105    */
 106   public static final String CONTROLLED_BY = "controlledBy";
 107
 108   /** Indicates that the label target group has changed. */
 109   public static final String LABEL_FOR_PROPERTY = "labelForProperty";
 110
 111   /** Indicates that the labelling objects have changed. */
 112   public static final String LABELED_BY_PROPERTY = "labeledByProperty";
 113
 114   /** Indicates that group membership has changed. */
 115   public static final String MEMBER_OF_PROPERTY = "memberOfProperty";
 116
 117   /** Indicates that the controller target group has changed. */
 118   public static final String CONTROLLER_FOR_PROPERTY = "controllerForProperty";
 119
 120   /** Indicates that the controlling objects have changed. */
 121   public static final String CONTROLLED_BY_PROPERTY = "controlledByProperty";
 122
 123   /** An empty set of targets. */
 124   private static final Object[] EMPTY_TARGETS = { };
 125
 126   /**
 127    * The related objects.
 128    *
 129    * @see #getTarget()
 130    * @see #setTarget(Object)
 131    * @see #setTarget(Object[])
 132    */
 133   Object[] targets;
 134
 135   /**
 136    * Create a new relation with a locale independent key, and no related
 137    * objects.
 138    *
 139    * @param key the name of the role
 140    * @see #toDisplayString(String, Locale)
 141    */
 142   public AccessibleRelation(String key)
 143   {
 144     this.key = key;
 145     targets = EMPTY_TARGETS;
 146   }
 147
 148   /**
 149    * Create a new relation with a locale independent key, and a single related
 150    * object.
 151    *
 152    * @param key the name of the role
 153    * @param target the related object
 154    * @see #toDisplayString(String, Locale)
 155    */
 156   public AccessibleRelation(String key, Object target)
 157   {
 158     this.key = key;
 159     targets = new Object[] { target };
 160   }
 161
 162   /**
 163    * Create a new relation with a locale independent key, and the given
 164    * related objects.
 165    *
 166    * @param key the name of the role
 167    * @param targets the related objects
 168    * @see #toDisplayString(String, Locale)
 169    */
 170   public AccessibleRelation(String key, Object[] targets)
 171   {
 172     this.key = key;
 173     this.targets = targets == null ? EMPTY_TARGETS : targets;
 174   }
 175
 176   /**
 177    * Return the key for this relation.
 178    *
 179    * @return the key
 180    * @see #CONTROLLER_FOR
 181    * @see #CONTROLLED_BY
 182    * @see #LABEL_FOR
 183    * @see #LABELED_BY
 184    * @see #MEMBER_OF
 185    */
 186   public String getKey()
 187   {
 188     return key;
 189   }
 190
 191   /**
 192    * Return the targets of this relation.
 193    *
 194    * @return the targets, may be empty, but never null
 195    */
 196   public Object[] getTarget()
 197   {
 198     return targets;
 199   }
 200
 201   /**
 202    * Set the target to a single object.
 203    *
 204    * @param target the new target
 205    */
 206   public void setTarget(Object target)
 207   {
 208     targets = new Object[] { target };
 209   }
 210
 211   /**
 212    * Set the target to an array of objects.
 213    *
 214    * @param targets the new targets
 215    */
 216   public void setTarget(Object[] targets)
 217   {
 218     this.targets = targets == null ? EMPTY_TARGETS : targets;
 219   }
 220 } // class AccessibleRelation