diff options
Diffstat (limited to 'israfil-foundation-collections/src/main/java/net/israfil/foundation/collections/RandomOrderIterable.java')
| -rw-r--r-- | israfil-foundation-collections/src/main/java/net/israfil/foundation/collections/RandomOrderIterable.java | 72 |
1 files changed, 72 insertions, 0 deletions
diff --git a/israfil-foundation-collections/src/main/java/net/israfil/foundation/collections/RandomOrderIterable.java b/israfil-foundation-collections/src/main/java/net/israfil/foundation/collections/RandomOrderIterable.java new file mode 100644 index 0000000..3b5656d --- /dev/null +++ b/israfil-foundation-collections/src/main/java/net/israfil/foundation/collections/RandomOrderIterable.java @@ -0,0 +1,72 @@ +/*
+ * 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);
+ }
+
+}
+
+
|
