/* * 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.geode.distributed.internal; import java.util.concurrent.LinkedBlockingQueue; import java.util.concurrent.TimeUnit; import java.util.Collection; /** * A LinkedBlockingQueue that supports stats. Named OverflowQueue for historical reasons. * */ public class OverflowQueueWithDMStats extends LinkedBlockingQueue { private static final long serialVersionUID = -1846248853494394996L; protected final QueueStatHelper stats; /** Creates new OverflowQueueWithDMStats */ public OverflowQueueWithDMStats(QueueStatHelper stats) { super(); this.stats = stats; } /** Creates new OverflowQueueWithDMStats with a maximum capacity. */ public OverflowQueueWithDMStats(int capacity, QueueStatHelper stats) { super(capacity); this.stats = stats; } @Override public boolean add(Object e) { preAdd(e); if (super.add(e)) { this.stats.add(); return true; } else { postRemove(e); return false; } } @Override public boolean offer(Object e) { preAdd(e); if (super.offer(e)) { this.stats.add(); return true; } else { postRemove(e); return false; } } @Override public void put(Object e) throws InterruptedException { if (Thread.interrupted()) throw new InterruptedException(); preAddInterruptibly(e); boolean didOp = false; try { super.put(e); didOp = true; this.stats.add(); } finally { if (!didOp) { postRemove(e); } } } @Override public boolean offer(Object e, long timeout, TimeUnit unit) throws InterruptedException { if (Thread.interrupted()) throw new InterruptedException(); preAddInterruptibly(e); boolean didOp = false; try { if (super.offer(e, timeout, unit)) { didOp = true; this.stats.add(); return true; } else { return false; } } finally { if (!didOp) { postRemove(e); } } } @Override public Object take() throws InterruptedException { if (Thread.interrupted()) throw new InterruptedException(); Object result = super.take(); postRemove(result); this.stats.remove(); return result; } @Override public Object poll(long timeout, TimeUnit unit) throws InterruptedException { if (Thread.interrupted()) throw new InterruptedException(); Object result = super.poll(timeout, unit); if (result != null) { postRemove(result); this.stats.remove(); } return result; } @Override public boolean remove(Object o) { if (super.remove(o)) { this.stats.remove(); postRemove(o); return true; } else { return false; } } @Override public int drainTo(Collection c) { int result = super.drainTo(c); if (result > 0) { this.stats.remove(result); postDrain(c); } return result; } @Override public int drainTo(Collection c, int maxElements) { int result = super.drainTo(c, maxElements); if (result > 0) { this.stats.remove(result); postDrain(c); } return result; } /** * Called before the specified object is added to this queue. */ protected void preAddInterruptibly(Object o) throws InterruptedException { // do nothing in this class. sub-classes can override } /** * Called before the specified object is added to this queue. */ protected void preAdd(Object o) { // do nothing in this class. sub-classes can override } /** * Called after the specified object is removed from this queue. */ protected void postRemove(Object o) { // do nothing in this class. sub-classes can override } /** * Called after the specified collection of objects have been drained (i.e. removed) from this * queue. */ protected void postDrain(Collection c) { // do nothing in this class. sub-classes can override } }