| /* AccessibleRelationSet.java -- the combined relations of an accessible object |
| Copyright (C) 2002, 2005 Free Software Foundation |
| |
| This file is part of GNU Classpath. |
| |
| GNU Classpath is free software; you can redistribute it and/or modify |
| it under the terms of the GNU General Public License as published by |
| the Free Software Foundation; either version 2, or (at your option) |
| any later version. |
| |
| GNU Classpath is distributed in the hope that it will be useful, but |
| WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| General Public License for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with GNU Classpath; see the file COPYING. If not, write to the |
| Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA |
| 02110-1301 USA. |
| |
| Linking this library statically or dynamically with other modules is |
| making a combined work based on this library. Thus, the terms and |
| conditions of the GNU General Public License cover the whole |
| combination. |
| |
| As a special exception, the copyright holders of this library give you |
| permission to link this library with independent modules to produce an |
| executable, regardless of the license terms of these independent |
| modules, and to copy and distribute the resulting executable under |
| terms of your choice, provided that you also meet, for each linked |
| independent module, the terms and conditions of the license of that |
| module. An independent module is a module which is not derived from |
| or based on this library. If you modify this library, you may extend |
| this exception to your version of the library, but you are not |
| obligated to do so. If you do not wish to do so, delete this |
| exception statement from your version. */ |
| |
| package javax.accessibility; |
| |
| import java.util.Locale; |
| import java.util.Vector; |
| |
| /** |
| * Describes all relations of an accessible object. For example, an object |
| * by labeled by one object and control another. |
| * |
| * @author Eric Blake (ebb9@email.byu.edu) |
| * @see AccessibleRelation |
| * @since 1.2 |
| * @status updated to 1.4 |
| */ |
| public class AccessibleRelationSet |
| { |
| /** |
| * The list of relations, should be instances of AccessibleRelation. Don't |
| * set this to null. |
| * |
| * @see #add(AccessibleRelation) |
| * @see #addAll(AccessibleRelation[]) |
| * @see #remove(AccessibleRelation) |
| * @see #contains(String) |
| * @see #get(String) |
| * @see #size() |
| * @see #toArray() |
| * @see #clear() |
| */ |
| protected Vector relations = new Vector(); |
| |
| /** |
| * Create an empty relation set. |
| */ |
| public AccessibleRelationSet() |
| { |
| } |
| |
| /** |
| * Create a relation set initialized with the given relations, duplicates are |
| * ignored. |
| * |
| * @param relations the relations to insert |
| * @throws NullPointerException if relations is null |
| */ |
| public AccessibleRelationSet(AccessibleRelation[] relations) |
| { |
| addAll(relations); |
| } |
| |
| /** |
| * Add a new relation to the current set. If the relation is already in |
| * the set, the targets are merged with the existing relation, possibly |
| * resulting in an object being in the target list more than once. Do not |
| * add a relation with a null key, as it will cause problems later. |
| * |
| * @param relation the relation to add |
| * @return true if the set was modified, which is always the case |
| * @throws NullPointerException if relation is null |
| */ |
| public boolean add(AccessibleRelation relation) |
| { |
| AccessibleRelation old = get(relation.key); |
| if (old == null) |
| return relations.add(relation); |
| if (old.targets.length == 0) |
| old.targets = relation.targets; |
| else if (relation.targets.length != 0) |
| { |
| Object[] t = new Object[old.targets.length + relation.targets.length]; |
| System.arraycopy(old.targets, 0, t, 0, old.targets.length); |
| System.arraycopy(relation.targets, 0, t, old.targets.length, |
| relation.targets.length); |
| old.targets = t; |
| } |
| return true; |
| } |
| |
| /** |
| * Add all of the relations to the current set. Duplicates are ignored. |
| * |
| * @param array the array of relations to add |
| * @throws NullPointerException if array is null or has null entries |
| */ |
| public void addAll(AccessibleRelation[] array) |
| { |
| int i = array.length; |
| while (--i >= 0) |
| add(array[i]); |
| } |
| |
| /** |
| * Remove a relation from the set. If a relation was removed, return true. |
| * Note that this uses AccessibleRelation.equals, which defaults to ==, so a |
| * relation with the same key may still exist in the set afterwords. |
| * |
| * @param relation the state to remove |
| * @return true if the set changed |
| */ |
| public boolean remove(AccessibleRelation relation) |
| { |
| return relations.remove(relation); |
| } |
| |
| /** |
| * Clear all relations in the set. |
| */ |
| public void clear() |
| { |
| relations.clear(); |
| } |
| |
| /** |
| * Return the number of relations in the set. |
| * |
| * @return the set size |
| */ |
| public int size() |
| { |
| return relations.size(); |
| } |
| |
| /** |
| * Check if the relation key is in the set. |
| * |
| * @param key the relation to locate |
| * @return true if it is in the set |
| */ |
| public boolean contains(String key) |
| { |
| int i = relations.size(); |
| while (--i >= 0) |
| if (((AccessibleRelation) relations.get(i)).key.equals(key)) |
| return true; |
| return false; |
| } |
| |
| /** |
| * Get the relation that matches the key. |
| * |
| * @param key the relation to locate |
| * @return the relation in the set, or null |
| */ |
| public AccessibleRelation get(String key) |
| { |
| int i = relations.size(); |
| while (--i >= 0) |
| { |
| AccessibleRelation r = (AccessibleRelation) relations.get(i); |
| if (r.key.equals(key)) |
| return r; |
| } |
| return null; |
| } |
| |
| /** |
| * Return the relation set as an array. |
| * |
| * @return an array of the current relations |
| */ |
| public AccessibleRelation[] toArray() |
| { |
| AccessibleRelation[] result = new AccessibleRelation[relations.size()]; |
| relations.toArray(result); |
| return result; |
| } |
| |
| /** |
| * Return a localized, comma-separated string representing all relations |
| * in the set. This is in arbitrary order. |
| * |
| * @return the string representation |
| * @see AccessibleBundle#toDisplayString(String, Locale) |
| */ |
| public String toString() |
| { |
| int i = relations.size(); |
| if (i == 0) |
| return ""; |
| // Pre-allocate an average of 10 chars per state. |
| StringBuffer b = new StringBuffer(i * 10); |
| while (--i >= 0) |
| b.append(relations.get(i)).append(','); |
| return b.substring(0, b.length() - 1); |
| } |
| } // class AccessibleRelationSet |