/*
***************************************************************************************
* Copyright (C) 2006 EsperTech, Inc. All rights reserved. *
* http://www.espertech.com/esper *
* http://www.espertech.com *
* ---------------------------------------------------------------------------------- *
* The software in this package is published under the terms of the GPL license *
* a copy of which has been included with this distribution in the license.txt file. *
***************************************************************************************
*/
package com.espertech.esper.collection;
import java.util.Enumeration;
/**
* Based on the {@link PermutationEnumeration} this enumeration provides, among a set of supplied integer
* values, all permutations of order these values can come in, ie.
* Example: {0, 2, 3} results in 6 enumeration values ending in {3, 2, 0}.
*/
public class NumberSetPermutationEnumeration implements Enumeration<int[]> {
private final int[] numberSet;
private final PermutationEnumeration permutationEnumeration;
/**
* Ctor.
*
* @param numberSet - set of integer numbers to permutate and provide each combination.
*/
public NumberSetPermutationEnumeration(int[] numberSet) {
this.numberSet = numberSet;
permutationEnumeration = new PermutationEnumeration(numberSet.length);
}
public boolean hasMoreElements() {
return permutationEnumeration.hasMoreElements();
}
public int[] nextElement() {
int[] permutation = permutationEnumeration.nextElement();
int[] result = new int[numberSet.length];
for (int i = 0; i < numberSet.length; i++) {
result[i] = numberSet[permutation[i]];
}
return result;
}
}