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/**
 * Copyright (c) 2000-2009 Liferay, Inc. All rights reserved.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

package com.liferay.portal.kernel.util;

import java.util.Iterator;
import java.util.LinkedHashSet;
import java.util.List;
import java.util.Random;
import java.util.Set;

/**
 * View Source
 *
 * @author Brian Wing Shun Chan
 *
 */
public class Randomizer extends Random {

	public static Randomizer getInstance() {
		return _instance;
	}

	public Randomizer() {
		super();
	}

	public Randomizer(long seed) {
		super(seed);
	}

	public int[] nextInt(int n, int size) {
		if (size > n) {
			size = n;
		}

		Set set = new LinkedHashSet();

		for (int i = 0; i < size; i++) {
			while (true) {
				Integer value = new Integer(nextInt(n));

				if (!set.contains(value)) {
					set.add(value);

					break;
				}
			}
		}

		int[] array = new int[set.size()];

		Iterator itr = set.iterator();

		for (int i = 0; i < array.length; i++) {
			array[i] = itr.next().intValue();
		}

		return array;
	}

	public void randomize(char array[]) {
		int length = array.length;

		for (int i = 0; i < length - 1; i++) {
			int x = nextInt(length);
			char y = array[i];

			array[i] = array[i + x];
			array[i + x] = y;

			length--;
		}
	}

	public void randomize(int array[]) {
		int length = array.length;

		for (int i = 0; i < length - 1; i++) {
			int x = nextInt(length);
			int y = array[i];

			array[i] = array[i + x];
			array[i + x] = y;

			length--;
		}
	}

	public void randomize(List