Repository: qpid-jms Updated Branches: refs/heads/master e3d21a7e6 -> 8b0993c9b
Add simple LRUCache implementation that can be used to cache anonymous producer instances for the AMQP provider. Project: http://git-wip-us.apache.org/repos/asf/qpid-jms/repo Commit: http://git-wip-us.apache.org/repos/asf/qpid-jms/commit/8b0993c9 Tree: http://git-wip-us.apache.org/repos/asf/qpid-jms/tree/8b0993c9 Diff: http://git-wip-us.apache.org/repos/asf/qpid-jms/diff/8b0993c9 Branch: refs/heads/master Commit: 8b0993c9b4ac079cff76411fd735a95f49cffe39 Parents: e3d21a7 Author: Timothy Bish <tabish...@gmail.com> Authored: Fri Oct 3 12:30:46 2014 -0400 Committer: Timothy Bish <tabish...@gmail.com> Committed: Fri Oct 3 12:31:18 2014 -0400 ---------------------------------------------------------------------- .../java/org/apache/qpid/jms/util/LRUCache.java | 99 ++++++++++++++++++++ .../org/apache/qpid/jms/util/LRUCacheTest.java | 98 +++++++++++++++++++ 2 files changed, 197 insertions(+) ---------------------------------------------------------------------- http://git-wip-us.apache.org/repos/asf/qpid-jms/blob/8b0993c9/qpid-jms-client/src/main/java/org/apache/qpid/jms/util/LRUCache.java ---------------------------------------------------------------------- diff --git a/qpid-jms-client/src/main/java/org/apache/qpid/jms/util/LRUCache.java b/qpid-jms-client/src/main/java/org/apache/qpid/jms/util/LRUCache.java new file mode 100644 index 0000000..76b130e --- /dev/null +++ b/qpid-jms-client/src/main/java/org/apache/qpid/jms/util/LRUCache.java @@ -0,0 +1,99 @@ +/** + * 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.qpid.jms.util; + +import java.util.LinkedHashMap; +import java.util.Map; + +/** + * A Simple LRU Cache based on a LinkedHashMap. + * + * @param <K> + * @param <V> + */ +public class LRUCache<K, V> extends LinkedHashMap<K, V> { + + private static final long serialVersionUID = -342098639681884413L; + protected int maxCacheSize = 10000; + + /** + * Default constructor for an LRU Cache The default capacity is 10000 + */ + public LRUCache() { + this(0,10000, 0.75f, true); + } + + /** + * Constructs a LRUCache with a maximum capacity + * + * @param maximumCacheSize + */ + public LRUCache(int maximumCacheSize) { + this(0, maximumCacheSize, 0.75f, true); + } + + /** + * Constructs an empty <tt>LRUCache</tt> instance with the specified + * initial capacity, maximumCacheSize,load factor and ordering mode. + * + * @param initialCapacity the initial capacity. + * @param maximumCacheSize + * @param loadFactor the load factor. + * @param accessOrder the ordering mode - <tt>true</tt> for access-order, + * <tt>false</tt> for insertion-order. + * + * @throws IllegalArgumentException if the initial capacity is negative or + * the load factor is non-positive. + */ + public LRUCache(int initialCapacity, int maximumCacheSize, float loadFactor, boolean accessOrder) { + super(initialCapacity, loadFactor, accessOrder); + this.maxCacheSize = maximumCacheSize; + } + + /** + * @return Returns the maxCacheSize. + */ + public int getMaxCacheSize() { + return maxCacheSize; + } + + /** + * @param maxCacheSize The maxCacheSize to set. + */ + public void setMaxCacheSize(int maxCacheSize) { + this.maxCacheSize = maxCacheSize; + } + + @Override + protected boolean removeEldestEntry(Map.Entry<K,V> eldest) { + if( size() > maxCacheSize ) { + onCacheEviction(eldest); + return true; + } + return false; + } + + /** + * Event point used by subclasses to perform some cleanup action when an + * element is evicted from the cache. + * + * @param eldest + * the item being evicted from the LRUCache. + */ + protected void onCacheEviction(Map.Entry<K,V> eldest) { + } +} http://git-wip-us.apache.org/repos/asf/qpid-jms/blob/8b0993c9/qpid-jms-client/src/test/java/org/apache/qpid/jms/util/LRUCacheTest.java ---------------------------------------------------------------------- diff --git a/qpid-jms-client/src/test/java/org/apache/qpid/jms/util/LRUCacheTest.java b/qpid-jms-client/src/test/java/org/apache/qpid/jms/util/LRUCacheTest.java new file mode 100644 index 0000000..ce3b08e --- /dev/null +++ b/qpid-jms-client/src/test/java/org/apache/qpid/jms/util/LRUCacheTest.java @@ -0,0 +1,98 @@ +/** + * 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.qpid.jms.util; + +import static org.junit.Assert.assertEquals; +import static org.junit.Assert.assertFalse; +import static org.junit.Assert.assertTrue; + +import java.util.ArrayList; +import java.util.List; + +import org.junit.Test; +import org.slf4j.Logger; +import org.slf4j.LoggerFactory; + +public class LRUCacheTest { + + protected static final Logger LOG = LoggerFactory.getLogger(LRUCacheTest.class); + + @Test + public void testResize() throws Exception { + LRUCache<Long, Long> underTest = new LRUCache<Long, Long>(1000); + + Long count = new Long(0); + long max = 0; + for (; count < 27276827; count++) { + long start = System.currentTimeMillis(); + if (!underTest.containsKey(count)) { + underTest.put(count, count); + } + long duration = System.currentTimeMillis() - start; + if (duration > max) { + LOG.info("count: " + count + ", new max=" + duration); + max = duration; + } + if (count % 100000000 == 0) { + LOG.info("count: " + count + ", max=" + max); + } + } + assertEquals("size is still in order", 1000, underTest.size()); + } + + @SuppressWarnings("serial") + @Test + public void testOnCacheEviction() { + + final int ENTRY_COUNT = 20; + + List<CacheEntry> entries = new ArrayList<CacheEntry>(); + LRUCache<String, CacheEntry> cache = new LRUCache<String, CacheEntry>(ENTRY_COUNT / 2) { + + @Override + protected void onCacheEviction(java.util.Map.Entry<String,CacheEntry> eldest) { + eldest.getValue().close(); + }; + }; + + for (int i = 0; i < ENTRY_COUNT; ++i) { + CacheEntry entry = new CacheEntry(); + entries.add(entry); + cache.put("Entry:" + i, entry); + } + + for (int i = 0; i < ENTRY_COUNT; ++i) { + if (i < ENTRY_COUNT / 2) { + assertFalse(entries.get(i).isOpen()); + } else { + assertTrue(entries.get(i).isOpen()); + } + } + } + + private static class CacheEntry { + private boolean open = true; + + public void close() { + this.open = false; + } + + public boolean isOpen() { + return open; + } + } +} --------------------------------------------------------------------- To unsubscribe, e-mail: commits-unsubscr...@qpid.apache.org For additional commands, e-mail: commits-h...@qpid.apache.org
