001    /* AccessibleRelation.java -- the relation between accessible objects
002       Copyright (C) 2002, 2005 Free Software Foundation
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    package javax.accessibility;
039    
040    import java.util.Locale;
041    
042    /**
043     * The relation between one accessible object and one or more other objects.
044     * For example, a button may control an action. An AccessibleRelationSet
045     * summarizes all relations of the object. This strongly typed "enumeration"
046     * supports localized strings. If the constants of this class are not
047     * adequate, new ones may be added in a similar matter.
048     *
049     * @author Eric Blake (ebb9@email.byu.edu)
050     * @since 1.2
051     * @status updated to 1.4
052     */
053    public class AccessibleRelation extends AccessibleBundle
054    {
055      /**
056       * Indicates the object labels other objects.
057       *
058       * @see #getTarget()
059       * @see #CONTROLLER_FOR
060       * @see #CONTROLLED_BY
061       * @see #LABELED_BY
062       * @see #MEMBER_OF
063       */
064      public static final String LABEL_FOR;
065    
066      /**
067       * Indicates the object is labeled by other objects.
068       *
069       * @see #getTarget()
070       * @see #CONTROLLER_FOR
071       * @see #CONTROLLED_BY
072       * @see #LABEL_FOR
073       * @see #MEMBER_OF
074       */
075      public static final String LABELED_BY;
076    
077      /**
078       * Indicates an object is a member of a group of target objects.
079       *
080       * @see #getTarget()
081       * @see #CONTROLLER_FOR
082       * @see #CONTROLLED_BY
083       * @see #LABEL_FOR
084       * @see #LABELED_BY
085       */
086      public static final String MEMBER_OF;
087    
088      /**
089       * Indicates an object is a controller for other objects.
090       *
091       * @see #getTarget()
092       * @see #CONTROLLED_BY
093       * @see #LABEL_FOR
094       * @see #LABELED_BY
095       * @see #MEMBER_OF
096       */
097      public static final String CONTROLLER_FOR;
098    
099      /**
100       * Indicates an object is controlled by other objects.
101       *
102       * @see #getTarget()
103       * @see #CONTROLLER_FOR
104       * @see #LABEL_FOR
105       * @see #LABELED_BY
106       * @see #MEMBER_OF
107       */
108      public static final String CONTROLLED_BY;
109    
110      /** Indicates that the label target group has changed. */
111      public static final String LABEL_FOR_PROPERTY = "labelForProperty";
112    
113      /** Indicates that the labelling objects have changed. */
114      public static final String LABELED_BY_PROPERTY = "labeledByProperty";
115    
116      /** Indicates that group membership has changed. */
117      public static final String MEMBER_OF_PROPERTY = "memberOfProperty";
118    
119      /** Indicates that the controller target group has changed. */
120      public static final String CONTROLLER_FOR_PROPERTY = "controllerForProperty";
121    
122      /** Indicates that the controlling objects have changed. */
123      public static final String CONTROLLED_BY_PROPERTY = "controlledByProperty";
124    
125      /**
126       * Indicates that an object is a child of another object.
127       * @since 1.5
128       */
129      public static final String CHILD_NODE_OF = "childNodeOf";
130    
131      /**
132       * Indicates that the ancestry relationship has changed.
133       * @since 1.5
134       */
135      public static final String CHILD_NODE_OF_PROPERTY = "childNodeOfProperty";
136    
137      /**
138       * Indicates that an object is embedded by another object.
139       * @since 1.5
140       */
141      public static final String EMBEDDED_BY = "embeddedBy";
142    
143      /**
144       * Indicates that the {@link #EMBEDDED_BY} property changed.
145       * @since 1.5
146       */
147      public static final String EMBEDDED_BY_PROPERTY = "embeddedByProperty";
148    
149      /**
150       * Indicates that an object embeds another object.
151       * @since 1.5
152       */
153      public static final String EMBEDS = "embeds";
154    
155      /**
156       * Indicates that the {@link #EMBEDS} property changed.
157       * @since 1.5
158       */
159      public static final String EMBEDS_PROPERTY = "embedsProperty";
160    
161      /**
162       * Indicates that one object directly follows another object,
163       * as in a paragraph flow.
164       * @since 1.5
165       */
166      public static final String FLOWS_FROM = "flowsFrom";
167    
168      /**
169       * Indicates that the {@link #FLOWS_FROM} property changed.
170       * @since 1.5
171       */
172      public static final String FLOWS_FROM_PROPERTY = "flowsFromProperty";
173    
174      /**
175       * Indicates that one object comes directly before another object,
176       * as in a paragraph flow.
177       * @since 1.5
178       */
179      public static final String FLOWS_TO = "flowsTo";
180    
181      /**
182       * Indicates that the {@link #FLOWS_TO} property changed.
183       * @since 1.5
184       */
185      public static final String FLOWS_TO_PROPERTY = "flowsToProperty";
186    
187      /**
188       * Indicates that one object is a parent window of another object.
189       * @since 1.5
190       */
191      public static final String PARENT_WINDOW_OF = "parentWindowOf";
192    
193      /**
194       * Indicates that the {@link #PARENT_WINDOW_OF} property changed.
195       * @since 1.5
196       */
197      public static final String PARENT_WINDOW_OF_PROPERTY = "parentWindowOfProperty";
198    
199      /**
200       * Indicates that one object is a subwindow of another object.
201       * @since 1.5
202       */
203      public static final String SUBWINDOW_OF = "subwindowOf";
204    
205      /**
206       * Indicates that the {@link #SUBWINDOW_OF} property changed.
207       * @since 1.5
208       */
209      public static final String SUBWINDOW_OF_PROPERTY = "subwindowOfProperty";
210    
211      /** An empty set of targets. */
212      private static final Object[] EMPTY_TARGETS = { };
213    
214      static
215        {
216          // not constants in JDK
217          LABEL_FOR = "labelFor";
218          LABELED_BY = "labeledBy";
219          MEMBER_OF = "memberOf";
220          CONTROLLER_FOR = "controllerFor";
221          CONTROLLED_BY = "controlledBy";
222        }
223    
224      /**
225       * The related objects.
226       *
227       * @see #getTarget()
228       * @see #setTarget(Object)
229       * @see #setTarget(Object[])
230       */
231      Object[] targets;
232    
233      /**
234       * Create a new relation with a locale independent key, and no related
235       * objects.
236       *
237       * @param key the name of the role
238       * @see #toDisplayString(String, Locale)
239       */
240      public AccessibleRelation(String key)
241      {
242        this.key = key;
243        targets = EMPTY_TARGETS;
244      }
245    
246      /**
247       * Create a new relation with a locale independent key, and a single related
248       * object.
249       *
250       * @param key the name of the role
251       * @param target the related object
252       * @see #toDisplayString(String, Locale)
253       */
254      public AccessibleRelation(String key, Object target)
255      {
256        this.key = key;
257        targets = new Object[] { target };
258      }
259    
260      /**
261       * Create a new relation with a locale independent key, and the given
262       * related objects.
263       *
264       * @param key the name of the role
265       * @param targets the related objects
266       * @see #toDisplayString(String, Locale)
267       */
268      public AccessibleRelation(String key, Object[] targets)
269      {
270        this.key = key;
271        this.targets = targets == null ? EMPTY_TARGETS : targets;
272      }
273    
274      /**
275       * Return the key for this relation.
276       *
277       * @return the key
278       * @see #CONTROLLER_FOR
279       * @see #CONTROLLED_BY
280       * @see #LABEL_FOR
281       * @see #LABELED_BY
282       * @see #MEMBER_OF
283       */
284      public String getKey()
285      {
286        return key;
287      }
288    
289      /**
290       * Return the targets of this relation.
291       *
292       * @return the targets, may be empty, but never null
293       */
294      public Object[] getTarget()
295      {
296        return targets;
297      }
298    
299      /**
300       * Set the target to a single object.
301       *
302       * @param target the new target
303       */
304      public void setTarget(Object target)
305      {
306        targets = new Object[] { target };
307      }
308    
309      /**
310       * Set the target to an array of objects.
311       *
312       * @param targets the new targets
313       */
314      public void setTarget(Object[] targets)
315      {
316        this.targets = targets == null ? EMPTY_TARGETS : targets;
317      }
318    } // class AccessibleRelation