/*
* 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.axis2.util.threadpool;
import org.apache.axis2.AxisFault;
import org.apache.axis2.i18n.Messages;
import org.apache.axis2.java.security.AccessController;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import java.security.PrivilegedActionException;
import java.security.PrivilegedExceptionAction;
import java.util.concurrent.Executor;
import java.util.concurrent.LinkedBlockingQueue;
import java.util.concurrent.SynchronousQueue;
import java.util.concurrent.ThreadPoolExecutor;
import java.util.concurrent.TimeUnit;
/**
* This the thread pool for axis2. This class will be used a singleton
* across axis2 engine. <code>ThreadPool</code> is accepts <code>AxisWorkers</code> which has
* run method on them and execute this method, using one of the threads
* in the thread pool.
*/
public class ThreadPool implements ThreadFactory {
private static final Log log = LogFactory.getLog(ThreadPool.class);
protected static long SLEEP_INTERVAL = 1000;
private static boolean shutDown;
protected ThreadPoolExecutor executor;
//integers that define the pool size, with the default values set.
private int corePoolSize = 5;
//max pool size is set to 100 to control the maximum number of threads created
private int maxPoolSize = 100;
public ThreadPool() {
setExecutor(createDefaultExecutor("Axis2 Task", Thread.NORM_PRIORITY, true));
}
public ThreadPool(int corePoolSize, int maxPoolSize) {
this.corePoolSize = corePoolSize;
this.maxPoolSize = maxPoolSize;
setExecutor(createDefaultExecutor("Axis2 Task", Thread.NORM_PRIORITY, true));
}
public Executor getExecutor() {
return executor;
}
public void setExecutor(ThreadPoolExecutor executor) {
this.executor = executor;
}
public void execute(Runnable worker) {
if (shutDown) {
throw new RuntimeException(Messages.getMessage("threadpoolshutdown"));
}
executor.execute(worker);
}
/**
* A forceful shutdown mechanism for thread pool.
*/
public void forceShutDown() {
if (log.isDebugEnabled()) {
log.debug("forceShutDown called. Thread workers will be stopped");
}
executor.shutdownNow();
}
/**
* This is the recommended shutdown method for the thread pool
* This will wait till all the workers that are already handed over to the
* thread pool get executed.
*
* @throws org.apache.axis2.AxisFault
*/
public void safeShutDown() throws AxisFault {
synchronized (this) {
shutDown = true;
}
executor.shutdown();
}
protected ThreadPoolExecutor createDefaultExecutor(final String name,
final int priority,
final boolean daemon) {
ThreadPoolExecutor rc;
if (maxPoolSize == Integer.MAX_VALUE) {
rc = new ThreadPoolExecutor(corePoolSize, maxPoolSize, 10,
TimeUnit.SECONDS, new SynchronousQueue(),
new DefaultThreadFactory(name, daemon, priority));
} else {
rc = new ThreadPoolExecutor(corePoolSize, maxPoolSize, 10,
TimeUnit.SECONDS, new LinkedBlockingQueue(),
new DefaultThreadFactory(name, daemon, priority));
}
// FIXME: This API is only in JDK 1.6 - Use reflection?
// rc.allowCoreThreadTimeOut(true);
return rc;
}
private static class DefaultThreadFactory implements java.util.concurrent.ThreadFactory {
private final String name;
private final boolean daemon;
private final int priority;
public DefaultThreadFactory(String name, boolean daemon, int priority) {
this.name = name;
this.daemon = daemon;
this.priority = priority;
}
public Thread newThread(
final Runnable runnable) {
// do the following section as privileged
// so that it will work even when java2 security
// has been enabled
Thread returnThread = null;
try {
returnThread = (Thread)
AccessController.doPrivileged(new PrivilegedExceptionAction<Thread>() {
public Thread run() {
Thread newThread =
new Thread(runnable, name);
newThread.setDaemon(daemon);
newThread.setPriority(priority);
return newThread;
}
}
);
}
catch (PrivilegedActionException e) {
// note: inner class can't have its own static log variable
if (log.isDebugEnabled()) {
log.debug("ThreadPoolExecutor.newThread(): Exception from AccessController [" + e.getClass()
.getName() + "] for [" + e.getMessage() + "]", e);
}
}
return returnThread;
}
}
}