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	/*
	* Copyright (c) 1999, 2013, Oracle and/or its affiliates. All rights reserved.
	* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
	*
	* This code is free software; you can redistribute it and/or modify it
	* under the terms of the GNU General Public License version 2 only, as
	* published by the Free Software Foundation. Oracle designates this
	* particular file as subject to the "Classpath" exception as provided
	* by Oracle in the LICENSE file that accompanied this code.
	*
	* This code 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
	* version 2 for more details (a copy is included in the LICENSE file that
	* accompanied this code).
	*
	* You should have received a copy of the GNU General Public License version
	* 2 along with this work; if not, write to the Free Software Foundation,
	* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
	*
	* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
	* or visit www.oracle.com if you need additional information or have any
	* questions.
	*/

	package javax.accessibility;

	import java.util.Vector;
	import java.util.Locale;
	import java.util.MissingResourceException;
	import java.util.ResourceBundle;

	/**
	* Class AccessibleRelationSet determines a component's relation set. The
	* relation set of a component is a set of AccessibleRelation objects that
	* describe the component's relationships with other components.
	*
	* @see AccessibleRelation
	*
	* @author Lynn Monsanto
	* @since 1.3
	*/
	public class AccessibleRelationSet {

	/**
	* Each entry in the Vector represents an AccessibleRelation.
	* @see #add
	* @see #addAll
	* @see #remove
	* @see #contains
	* @see #get
	* @see #size
	* @see #toArray
	* @see #clear
	*/
	protected Vector<AccessibleRelation> relations = null;

	/**
	* Creates a new empty relation set.
	*/
	public AccessibleRelationSet() {
	relations = null;
	}

	/**
	* Creates a new relation with the initial set of relations contained in
	* the array of relations passed in. Duplicate entries are ignored.
	*
	* @param relations an array of AccessibleRelation describing the
	* relation set.
	*/
	public AccessibleRelationSet(AccessibleRelation[] relations) {
	if (relations.length != 0) {
	this.relations = new Vector(relations.length);
	for (int i = 0; i < relations.length; i++) {
	add(relations[i]);
	}
	}
	}

	/**
	* Adds a new relation to the current relation set. If the relation
	* is already in the relation set, the target(s) of the specified
	* relation is merged with the target(s) of the existing relation.
	* Otherwise, the new relation is added to the relation set.
	*
	* @param relation the relation to add to the relation set
	* @return true if relation is added to the relation set; false if the
	* relation set is unchanged
	*/
	public boolean add(AccessibleRelation relation) {
	if (relations == null) {
	relations = new Vector();
	}

	// Merge the relation targets if the key exists
	AccessibleRelation existingRelation = get(relation.getKey());
	if (existingRelation == null) {
	relations.addElement(relation);
	return true;
	} else {
	Object [] existingTarget = existingRelation.getTarget();
	Object [] newTarget = relation.getTarget();
	int mergedLength = existingTarget.length + newTarget.length;
	Object [] mergedTarget = new Object[mergedLength];
	for (int i = 0; i < existingTarget.length; i++) {
	mergedTarget[i] = existingTarget[i];
	}
	for (int i = existingTarget.length, j = 0;
	i < mergedLength;
	i++, j++) {
	mergedTarget[i] = newTarget[j];
	}
	existingRelation.setTarget(mergedTarget);
	}
	return true;
	}

	/**
	* Adds all of the relations to the existing relation set. Duplicate
	* entries are ignored.
	*
	* @param relations AccessibleRelation array describing the relation set.
	*/
	public void addAll(AccessibleRelation[] relations) {
	if (relations.length != 0) {
	if (this.relations == null) {
	this.relations = new Vector(relations.length);
	}
	for (int i = 0; i < relations.length; i++) {
	add(relations[i]);
	}
	}
	}

	/**
	* Removes a relation from the current relation set. If the relation
	* is not in the set, the relation set will be unchanged and the
	* return value will be false. If the relation is in the relation
	* set, it will be removed from the set and the return value will be
	* true.
	*
	* @param relation the relation to remove from the relation set
	* @return true if the relation is in the relation set; false if the
	* relation set is unchanged
	*/
	public boolean remove(AccessibleRelation relation) {
	if (relations == null) {
	return false;
	} else {
	return relations.removeElement(relation);
	}
	}

	/**
	* Removes all the relations from the current relation set.
	*/
	public void clear() {
	if (relations != null) {
	relations.removeAllElements();
	}
	}

	/**
	* Returns the number of relations in the relation set.
	* @return the number of relations in the relation set
	*/
	public int size() {
	if (relations == null) {
	return 0;
	} else {
	return relations.size();
	}
	}

	/**
	* Returns whether the relation set contains a relation
	* that matches the specified key.
	* @param key the AccessibleRelation key
	* @return true if the relation is in the relation set; otherwise false
	*/
	public boolean contains(String key) {
	return get(key) != null;
	}

	/**
	* Returns the relation that matches the specified key.
	* @param key the AccessibleRelation key
	* @return the relation, if one exists, that matches the specified key.
	* Otherwise, null is returned.
	*/
	public AccessibleRelation get(String key) {
	if (relations == null) {
	return null;
	} else {
	int len = relations.size();
	for (int i = 0; i < len; i++) {
	AccessibleRelation relation =
	(AccessibleRelation)relations.elementAt(i);
	if (relation != null && relation.getKey().equals(key)) {
	return relation;
	}
	}
	return null;
	}
	}

	/**
	* Returns the current relation set as an array of AccessibleRelation
	* @return AccessibleRelation array contacting the current relation.
	*/
	public AccessibleRelation[] toArray() {
	if (relations == null) {
	return new AccessibleRelation[0];
	} else {
	AccessibleRelation[] relationArray
	= new AccessibleRelation[relations.size()];
	for (int i = 0; i < relationArray.length; i++) {
	relationArray[i] = (AccessibleRelation) relations.elementAt(i);
	}
	return relationArray;
	}
	}

	/**
	* Creates a localized String representing all the relations in the set
	* using the default locale.
	*
	* @return comma separated localized String
	* @see AccessibleBundle#toDisplayString
	*/
	public String toString() {
	String ret = "";
	if ((relations != null) && (relations.size() > 0)) {
	ret = ((AccessibleRelation) (relations.elementAt(0))).toDisplayString();
	for (int i = 1; i < relations.size(); i++) {
	ret = ret + ","
	+ ((AccessibleRelation) (relations.elementAt(i))).
	toDisplayString();
	}
	}
	return ret;
	}
	}

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