Author: ggregory
Date: Wed Nov 9 14:34:43 2011
New Revision: 1199773
URL: http://svn.apache.org/viewvc?rev=1199773&view=rev
Log:
[LANG-762] Handle or document ReflectionToStringBuilder and ToStringBuilder for
collections that are not thread safe.
Added:
commons/proper/lang/trunk/src/test/java/org/apache/commons/lang3/builder/ToStringStyleConcurrencyTest.java
Added:
commons/proper/lang/trunk/src/test/java/org/apache/commons/lang3/builder/ToStringStyleConcurrencyTest.java
URL:
http://svn.apache.org/viewvc/commons/proper/lang/trunk/src/test/java/org/apache/commons/lang3/builder/ToStringStyleConcurrencyTest.java?rev=1199773&view=auto
==============================================================================
---
commons/proper/lang/trunk/src/test/java/org/apache/commons/lang3/builder/ToStringStyleConcurrencyTest.java
(added)
+++
commons/proper/lang/trunk/src/test/java/org/apache/commons/lang3/builder/ToStringStyleConcurrencyTest.java
Wed Nov 9 14:34:43 2011
@@ -0,0 +1,108 @@
+/*
+ * 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.lang3.builder;
+
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.LinkedList;
+import java.util.List;
+import java.util.concurrent.Callable;
+import java.util.concurrent.CopyOnWriteArrayList;
+import java.util.concurrent.ExecutionException;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+import java.util.concurrent.Future;
+
+import org.junit.Test;
+
+/**
+ * Tests concurrent access for the default {@link ToStringStyle}.
+ * <p>
+ * The {@link ToStringStyle} class includes a registry to avoid infinite loops
for objects with circular references. We
+ * want to make sure that we do not get concurrency exceptions accessing this
registry.
+ * </p>
+ * <p>
+ * This test passes but only tests one aspect of the issue.
+ * </p>
+ *
+ * @see <a href="https://issues.apache.org/jira/browse/LANG-762";>[LANG-762]
Handle or document ReflectionToStringBuilder
+ * and ToStringBuilder for collections that are not thread safe</a>
+ * @since 3.0.2
+ */
+public class ToStringStyleConcurrencyTest {
+
+ static class CollectionHolder<T extends Collection<?>> {
+ T collection;
+
+ CollectionHolder(T collection) {
+ this.collection = collection;
+ }
+ }
+
+ private static final List<Integer> LIST;
+ private static final int LIST_SIZE = 100000;
+ private static final int REPEAT = 100;
+
+ static {
+ LIST = new ArrayList<Integer>(LIST_SIZE);
+ for (int i = 0; i < LIST_SIZE; i++) {
+ LIST.add(Integer.valueOf(i));
+ }
+ }
+
+ @Test
+ public void testLinkedList() throws InterruptedException,
ExecutionException {
+ this.testConcurrency(new CollectionHolder<List<Integer>>(new
LinkedList<Integer>()));
+ }
+
+ @Test
+ public void testArrayList() throws InterruptedException,
ExecutionException {
+ this.testConcurrency(new CollectionHolder<List<Integer>>(new
ArrayList<Integer>()));
+ }
+
+ @Test
+ public void testCopyOnWriteArrayList() throws InterruptedException,
ExecutionException {
+ this.testConcurrency(new CollectionHolder<List<Integer>>(new
CopyOnWriteArrayList<Integer>()));
+ }
+
+ private void testConcurrency(final CollectionHolder<List<Integer>> holder)
throws InterruptedException,
+ ExecutionException {
+ final List<Integer> list = holder.collection;
+ // make a big array that takes a long time to toString()
+ list.addAll(LIST);
+ // Create a thread pool with two threads to cause the most contention
on the underlying resource.
+ final ExecutorService threadPool = Executors.newFixedThreadPool(2);
+ // Consumes toStrings
+ Callable<Integer> consumer = new Callable<Integer>() {
+ public Integer call() {
+ for (int i = 0; i < REPEAT; i++) {
+ // Calls ToStringStyle
+ new ToStringBuilder(holder).append(holder.collection);
+ }
+ return REPEAT;
+ }
+ };
+ Collection<Callable<Integer>> tasks = new
ArrayList<Callable<Integer>>();
+ tasks.add(consumer);
+ tasks.add(consumer);
+ final List<Future<Integer>> futures = threadPool.invokeAll(tasks);
+ for (Future<Integer> future : futures) {
+ future.get();
+ }
+ }
+}
