/*
* Licensed under the GPL License. You may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://probe.jstripe.com/d/license.shtml
*
* THIS PACKAGE IS PROVIDED "AS IS" AND WITHOUT ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
* WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
*/
package org.frameworkset.util.tokenizer;
import java.util.*;
/**
* <code>UniqueList</code> is a successor of <code>java.util.Vector</code> to provide a collection that
* contains no duplicate elements, more formally such that e1.compareTo(e2) == 0. <p>
*
* As from above, the collection implies that all its elements must implement <code>Comparable</code> interface.
* <p>
* The collection is kept ordered whenever elements added or removed and besides uniqueness it is to provide fast
* element search based again on e1.compareTo(e2) values.
*
* @author Vlad Ilyushchenko
*/
public class UniqueList extends Vector {
public synchronized boolean add(Object obj) {
return add(obj, null);
}
protected synchronized boolean add(Object obj, Comparator c) {
if (size() == 0)
return super.add(obj);
else {
int index;
index = c == null ? Collections.binarySearch(this, obj) : Collections.binarySearch(this, obj, c);
if (index < 0) {
if (-index - 1 >= size())
super.add(obj);
else
super.insertElementAt(obj, -index - 1);
}
return index < 0;
}
}
public synchronized void insertElementAt(Object obj, int index) {
add(obj);
}
public synchronized boolean addAll(Collection c) {
boolean ok = this != c;
if (ok) {
Iterator iterator = c.iterator();
while (iterator.hasNext()) {
ok = this.add(iterator.next()) && ok;
}
}
return ok;
}
}