/*
* @(#)AccessibleRelationSet.java 1.15 06/04/07
*
* Copyright 2006 Sun Microsystems, Inc. All rights reserved.
* SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
*/
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
*
* @version 1.15 04/07/06
* @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.
*/
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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