Repository: commons-collections Updated Branches: refs/heads/master 611c73889 -> c6dc370ab
[COLLECTIONS-575] Synchronized queue wrapper in QueueUtils. Project: http://git-wip-us.apache.org/repos/asf/commons-collections/repo Commit: http://git-wip-us.apache.org/repos/asf/commons-collections/commit/c6dc370a Tree: http://git-wip-us.apache.org/repos/asf/commons-collections/tree/c6dc370a Diff: http://git-wip-us.apache.org/repos/asf/commons-collections/diff/c6dc370a Branch: refs/heads/master Commit: c6dc370abbbf0b487a13bd7f564287a41755bf71 Parents: 611c738 Author: Gary Gregory <ggreg...@apache.org> Authored: Tue Jan 2 19:49:41 2018 -0700 Committer: Gary Gregory <ggreg...@apache.org> Committed: Tue Jan 2 19:49:41 2018 -0700 ---------------------------------------------------------------------- src/changes/changes.xml | 3 + .../apache/commons/collections4/QueueUtils.java | 32 +++++ .../collections4/queue/SynchronizedQueue.java | 143 +++++++++++++++++++ .../commons/collections4/QueueUtilsTest.java | 17 ++- .../queue/SynchronizedQueueTest.java | 63 ++++++++ ...hronizedQueue.emptyCollection.version4.2.obj | Bin 0 -> 271 bytes ...chronizedQueue.fullCollection.version4.2.obj | Bin 0 -> 678 bytes 7 files changed, 257 insertions(+), 1 deletion(-) ---------------------------------------------------------------------- http://git-wip-us.apache.org/repos/asf/commons-collections/blob/c6dc370a/src/changes/changes.xml ---------------------------------------------------------------------- diff --git a/src/changes/changes.xml b/src/changes/changes.xml index eb6ab22..8d68c42 100644 --- a/src/changes/changes.xml +++ b/src/changes/changes.xml @@ -75,6 +75,9 @@ <action issue="COLLECTIONS-668" dev="ggregory" type="add" due-to="Gary Gregory"> Add CollectionUtils containsAny method for primitive array: org.apache.commons.collections4.CollectionUtils.containsAny(Collection<?>, T...). </action> + <action issue="COLLECTIONS-575" dev="ggregory" type="add" due-to="Guram Savinov, Grzegorz Rożniecki, Bruno P. Kinoshita, Gary Gregory"> + Synchronized queue wrapper in QueueUtils. + </action> </release> <release version="4.1" date="2015-11-28" description="This is a security and minor release."> <action issue="COLLECTIONS-508" dev="tn" type="add"> http://git-wip-us.apache.org/repos/asf/commons-collections/blob/c6dc370a/src/main/java/org/apache/commons/collections4/QueueUtils.java ---------------------------------------------------------------------- diff --git a/src/main/java/org/apache/commons/collections4/QueueUtils.java b/src/main/java/org/apache/commons/collections4/QueueUtils.java index 053581c..ee4114b 100644 --- a/src/main/java/org/apache/commons/collections4/QueueUtils.java +++ b/src/main/java/org/apache/commons/collections4/QueueUtils.java @@ -20,6 +20,7 @@ import java.util.LinkedList; import java.util.Queue; import org.apache.commons.collections4.queue.PredicatedQueue; +import org.apache.commons.collections4.queue.SynchronizedQueue; import org.apache.commons.collections4.queue.TransformedQueue; import org.apache.commons.collections4.queue.UnmodifiableQueue; @@ -44,6 +45,37 @@ public class QueueUtils { //----------------------------------------------------------------------- /** + * Returns a synchronized (thread-safe) queue backed by the given queue. + * In order to guarantee serial access, it is critical that all access to the + * backing queue is accomplished through the returned queue. + * <p> + * It is imperative that the user manually synchronize on the returned queue + * when iterating over it: + * + * <pre> + * Queue queue = QueueUtils.synchronizedQueue(new CircularFifoQueue()); + * ... + * synchronized(queue) { + * Iterator i = queue.iterator(); // Must be in synchronized block + * while (i.hasNext()) + * foo(i.next()); + * } + * } + * </pre> + * + * Failure to follow this advice may result in non-deterministic behavior. + * + * @param <E> the element type + * @param queue the queue to synchronize, must not be null + * @return a synchronized queue backed by that queue + * @throws NullPointerException if the queue is null + * @since 4.2 + */ + public static <E> Queue<E> synchronizedQueue(final Queue<E> queue) { + return SynchronizedQueue.synchronizedQueue(queue); + } + + /** * Returns an unmodifiable queue backed by the given queue. * * @param <E> the type of the elements in the queue http://git-wip-us.apache.org/repos/asf/commons-collections/blob/c6dc370a/src/main/java/org/apache/commons/collections4/queue/SynchronizedQueue.java ---------------------------------------------------------------------- diff --git a/src/main/java/org/apache/commons/collections4/queue/SynchronizedQueue.java b/src/main/java/org/apache/commons/collections4/queue/SynchronizedQueue.java new file mode 100644 index 0000000..5eda57f --- /dev/null +++ b/src/main/java/org/apache/commons/collections4/queue/SynchronizedQueue.java @@ -0,0 +1,143 @@ +/* + * Licensed to the Apache Software Foundation (ASF) under one or more + * contributor license agreements. See the NOTICE file distributed with + * this work for additional information regarding copyright ownership. + * The ASF licenses this file to You under the Apache License, Version 2.0 + * (the "License"); you may not use this file except in compliance with + * the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ +package org.apache.commons.collections4.queue; + +import java.util.Queue; + +import org.apache.commons.collections4.collection.SynchronizedCollection; + +/** + * Decorates another {@link Queue} to synchronize its behaviour for a multi-threaded environment. + * <p> + * Methods are synchronized, then forwarded to the decorated queue. Iterators must be separately synchronized around the + * loop. + * + * @param <E> the type of the elements in the collection + * @since 4.2 + */ +public class SynchronizedQueue<E> extends SynchronizedCollection<E> implements Queue<E> { + + /** Serialization version */ + private static final long serialVersionUID = 1L; + + /** + * Factory method to create a synchronized queue. + * + * @param <E> + * the type of the elements in the queue + * @param queue + * the queue to decorate, must not be null + * @return a new synchronized Queue + * @throws NullPointerException + * if queue is null + */ + public static <E> SynchronizedQueue<E> synchronizedQueue(final Queue<E> queue) { + return new SynchronizedQueue<E>(queue); + } + + // ----------------------------------------------------------------------- + /** + * Constructor that wraps (not copies). + * + * @param queue + * the queue to decorate, must not be null + * @throws NullPointerException + * if queue is null + */ + protected SynchronizedQueue(final Queue<E> queue) { + super(queue); + } + + /** + * Constructor that wraps (not copies). + * + * @param queue + * the queue to decorate, must not be null + * @param lock + * the lock to use, must not be null + * @throws NullPointerException + * if queue or lock is null + */ + protected SynchronizedQueue(final Queue<E> queue, final Object lock) { + super(queue, lock); + } + + /** + * Gets the queue being decorated. + * + * @return the decorated queue + */ + @Override + protected Queue<E> decorated() { + return (Queue<E>) super.decorated(); + } + + @Override + public E element() { + synchronized (lock) { + return decorated().element(); + } + } + + @Override + public boolean equals(final Object object) { + if (object == this) { + return true; + } + synchronized (lock) { + return decorated().equals(object); + } + } + + // ----------------------------------------------------------------------- + + @Override + public int hashCode() { + synchronized (lock) { + return decorated().hashCode(); + } + } + + @Override + public boolean offer(final E e) { + synchronized (lock) { + return decorated().offer(e); + } + } + + @Override + public E peek() { + synchronized (lock) { + return decorated().peek(); + } + } + + @Override + public E poll() { + synchronized (lock) { + return decorated().poll(); + } + } + + @Override + public E remove() { + synchronized (lock) { + return decorated().remove(); + } + } + +} http://git-wip-us.apache.org/repos/asf/commons-collections/blob/c6dc370a/src/test/java/org/apache/commons/collections4/QueueUtilsTest.java ---------------------------------------------------------------------- diff --git a/src/test/java/org/apache/commons/collections4/QueueUtilsTest.java b/src/test/java/org/apache/commons/collections4/QueueUtilsTest.java index 970f9ce..d75c321 100644 --- a/src/test/java/org/apache/commons/collections4/QueueUtilsTest.java +++ b/src/test/java/org/apache/commons/collections4/QueueUtilsTest.java @@ -16,13 +16,16 @@ */ package org.apache.commons.collections4; -import static org.junit.Assert.*; +import static org.junit.Assert.assertSame; +import static org.junit.Assert.assertTrue; +import static org.junit.Assert.fail; import java.util.LinkedList; import java.util.Queue; import org.apache.commons.collections4.functors.TruePredicate; import org.apache.commons.collections4.queue.PredicatedQueue; +import org.apache.commons.collections4.queue.SynchronizedQueue; import org.apache.commons.collections4.queue.TransformedQueue; import org.apache.commons.collections4.queue.UnmodifiableQueue; import org.junit.Test; @@ -39,6 +42,18 @@ public class QueueUtilsTest { // ---------------------------------------------------------------------- @Test + public void testSynchronizedQueue() { + Queue<Object> queue = QueueUtils.synchronizedQueue(new LinkedList<Object>()); + assertTrue("Returned object should be a SynchronizedQueue.", queue instanceof SynchronizedQueue); + try { + QueueUtils.synchronizedQueue(null); + fail("Expecting NullPointerException for null queue."); + } catch (final NullPointerException ex) { + // expected + } + } + + @Test public void testUnmodifiableQueue() { Queue<Object> queue = QueueUtils.unmodifiableQueue(new LinkedList<>()); assertTrue("Returned object should be an UnmodifiableQueue.", queue instanceof UnmodifiableQueue); http://git-wip-us.apache.org/repos/asf/commons-collections/blob/c6dc370a/src/test/java/org/apache/commons/collections4/queue/SynchronizedQueueTest.java ---------------------------------------------------------------------- diff --git a/src/test/java/org/apache/commons/collections4/queue/SynchronizedQueueTest.java b/src/test/java/org/apache/commons/collections4/queue/SynchronizedQueueTest.java new file mode 100644 index 0000000..a48f0ac --- /dev/null +++ b/src/test/java/org/apache/commons/collections4/queue/SynchronizedQueueTest.java @@ -0,0 +1,63 @@ +/* + * Licensed to the Apache Software Foundation (ASF) under one or more + * contributor license agreements. See the NOTICE file distributed with + * this work for additional information regarding copyright ownership. + * The ASF licenses this file to You under the Apache License, Version 2.0 + * (the "License"); you may not use this file except in compliance with + * the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ +package org.apache.commons.collections4.queue; + +import java.util.LinkedList; +import java.util.Queue; + +import org.apache.commons.collections4.BulkTest; +import org.junit.Ignore; + +import junit.framework.Test; + +/** + * Extension of {@link AbstractQueueTest} for exercising the + * {@link SynchronizedQueue} implementation. + * + * @since 4.2 + */ +public class SynchronizedQueueTest<T> extends AbstractQueueTest<T> { + + public static Test suite() { + return BulkTest.makeSuite(SynchronizedQueueTest.class); + } + + public SynchronizedQueueTest(final String testName) { + super(testName); + } + + //----------------------------------------------------------------------- + + @Override + public String getCompatibilityVersion() { + return "4.2"; + } + + @Override + public Queue<T> makeObject() { + return SynchronizedQueue.synchronizedQueue(new LinkedList<T>()); + } + + @Ignore("Run once") + public void testCreate() throws Exception { + Queue<T> queue = makeObject(); + writeExternalFormToDisk((java.io.Serializable) queue, "src/test/resources/data/test/SynchronizedQueue.emptyCollection.version4.2.obj"); + queue = makeFullCollection(); + writeExternalFormToDisk((java.io.Serializable) queue, "src/test/resources/data/test/SynchronizedQueue.fullCollection.version4.2.obj"); + } + +} http://git-wip-us.apache.org/repos/asf/commons-collections/blob/c6dc370a/src/test/resources/data/test/SynchronizedQueue.emptyCollection.version4.2.obj ---------------------------------------------------------------------- diff --git a/src/test/resources/data/test/SynchronizedQueue.emptyCollection.version4.2.obj b/src/test/resources/data/test/SynchronizedQueue.emptyCollection.version4.2.obj new file mode 100644 index 0000000..96c1df5 Binary files /dev/null and b/src/test/resources/data/test/SynchronizedQueue.emptyCollection.version4.2.obj differ http://git-wip-us.apache.org/repos/asf/commons-collections/blob/c6dc370a/src/test/resources/data/test/SynchronizedQueue.fullCollection.version4.2.obj ---------------------------------------------------------------------- diff --git a/src/test/resources/data/test/SynchronizedQueue.fullCollection.version4.2.obj b/src/test/resources/data/test/SynchronizedQueue.fullCollection.version4.2.obj new file mode 100644 index 0000000..f8cde0f Binary files /dev/null and b/src/test/resources/data/test/SynchronizedQueue.fullCollection.version4.2.obj differ
