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/*
* Copyright (c) 2007 Israfil Consulting Services Corporation
* Copyright (c) 2007 Christian Edward Gruber
* All Rights Reserved
*
* This software is licensed under the Berkeley Standard Distribution license,
* (BSD license), as defined below:
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
* 3. Neither the name of Israfil Consulting Services nor the names of its contributors
* may be used to endorse or promote products derived from this software without
* specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
* INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA,
* OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
* OF SUCH DAMAGE.
*
* $Id: IterableResultSet.java 26 2006-02-13 16:35:44Z cgruber $
*/
package net.israfil.foundation.collections;
import java.security.SecureRandom;
import java.util.Collection;
import java.util.Iterator;
import java.util.Random;
/**
* A simple wrapper that provides an Iterable implementation that wraps
* a collection and returns a RandomOrderIterator when asked for an iterator.
*
* No result set can have more than one Iterable wrapper around it at a time.
* However, it is impossible for this object to know implicitly when it is
* no longer required (to free the reference). Therefore, when this
* wrapper is concluded, it should be disposed of via the dispose() method.
*
* @author <a href="mailto:cgruber@israfil.net">Christian Edward Gruber </a>
*/
public class RandomOrderIterable<E> implements Iterable<E> {
private Collection<E> _collection;
private Random _random = null;
public RandomOrderIterable(Collection<E> collection) {
_collection = collection;
}
public RandomOrderIterable(Collection<E> collection, Random random) {
this(collection);
_random = random;
}
public Iterator<E> iterator() {
return new RandomOrderIterator<E>(_collection,(_random == null) ? new SecureRandom() : _random);
}
}
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