/*
* Copyright (c) 1998-2011 Caucho Technology -- all rights reserved
*
* This file is part of Resin(R) Open Source
*
* Each copy or derived work must preserve the copyright notice and this
* notice unmodified.
*
* Resin Open Source is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* Resin Open Source is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE, or any warranty
* of NON-INFRINGEMENT. See the GNU General Public License for more
* details.
*
* You should have received a copy of the GNU General Public License
* along with Resin Open Source; if not, write to the
*
* Free Software Foundation, Inc.
* 59 Temple Place, Suite 330
* Boston, MA 02111-1307 USA
*
* @author Scott Ferguson
*/
package com.caucho.server.util;
import java.util.Collection;
import java.util.HashSet;
import java.util.Iterator;
import java.util.List;
import java.util.Set;
import java.util.Timer;
import java.util.concurrent.Callable;
import java.util.concurrent.CancellationException;
import java.util.concurrent.Delayed;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.Future;
import java.util.concurrent.ScheduledExecutorService;
import java.util.concurrent.ScheduledFuture;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.TimeoutException;
import java.util.logging.Level;
import java.util.logging.Logger;
import com.caucho.config.inject.SingletonBindingHandle;
import com.caucho.env.thread.ThreadPool;
import com.caucho.loader.Environment;
import com.caucho.loader.EnvironmentClassLoader;
import com.caucho.loader.EnvironmentListener;
import com.caucho.loader.EnvironmentLocal;
import com.caucho.util.Alarm;
import com.caucho.util.AlarmListener;
import com.caucho.util.L10N;
/**
* Scheduler for custom services.
*/
public class ScheduledThreadPool implements ScheduledExecutorService,
EnvironmentListener, java.io.Serializable {
private static final long serialVersionUID = 1L;
private static Logger log
= Logger.getLogger(ScheduledThreadPool.class.getName());
private static L10N L = new L10N(ScheduledThreadPool.class);
private static EnvironmentLocal<ScheduledThreadPool> _local = new EnvironmentLocal<ScheduledThreadPool>();
private ThreadPool _threadPool;
private boolean _isShutdown;
private boolean _isTerminated;
private ClassLoader _loader;
@SuppressWarnings("unchecked")
private final Set<Future> _futureSet = new HashSet<Future>();
private ScheduledThreadPool()
{
_loader = Thread.currentThread().getContextClassLoader();
_threadPool = ThreadPool.getThreadPool();
if (_threadPool == null)
throw new NullPointerException();
Environment.addEnvironmentListener(this);
}
public static ScheduledThreadPool getLocal()
{
synchronized (_local) {
ScheduledThreadPool pool = _local.getLevel();
if (pool == null) {
pool = new ScheduledThreadPool();
_local.set(pool);
}
return pool;
}
}
//
// Executor
//
/**
* Launches a thread to execute a command.
*/
@SuppressWarnings("unchecked")
public void execute(Runnable command)
{
if (_isShutdown)
throw new IllegalStateException("ThreadPool has closed");
TaskFuture future = new TaskFuture(_loader, command, null);
synchronized (_futureSet) {
_futureSet.add(future);
_threadPool.scheduleExecutorTask(future);
}
}
//
// ExecutorService
//
/**
* Blocks until the tasks complete.
*/
@Override
public boolean awaitTermination(long timeout, TimeUnit unit)
{
throw new UnsupportedOperationException();
}
/**
* Invokes a set of tasks.
*/
@Override
@SuppressWarnings("unchecked")
public List invokeAll(Collection tasks)
{
throw new UnsupportedOperationException();
}
/**
* Invokes a set of tasks.
*/
@Override
@SuppressWarnings("unchecked")
public List invokeAll(Collection tasks, long timeout, TimeUnit unit)
{
// XXX: todo
throw new UnsupportedOperationException();
}
/**
* Invokes a set of tasks.
*/
@Override
@SuppressWarnings("unchecked")
public Object invokeAny(Collection tasks)
{
// XXX: todo
throw new UnsupportedOperationException();
}
/**
* Invokes a set of tasks.
*/
@SuppressWarnings("unchecked")
public Object invokeAny(Collection tasks, long timeout, TimeUnit unit)
{
// XXX: todo
throw new UnsupportedOperationException();
}
/**
* Return true if the executor is shut down.
*/
@Override
public boolean isShutdown()
{
return _isShutdown;
}
/**
* Return true if the executor has completed shutting down.
*/
@Override
public boolean isTerminated()
{
return _isTerminated;
}
/**
* Starts the shutdown.
*/
@Override
public void shutdown()
{
throw new UnsupportedOperationException();
}
/**
* Starts the shutdown.
*/
@Override
public List<Runnable> shutdownNow()
{
throw new UnsupportedOperationException();
}
/**
* Submits a task for execution.
*/
@Override
public <T> Future<T> submit(Callable<T> task)
{
if (_isShutdown)
throw new IllegalStateException("ThreadPool has closed");
TaskFuture<T> future = new TaskFuture<T>(_loader, task);
synchronized (_futureSet) {
_futureSet.add(future);
_threadPool.scheduleExecutorTask(future);
}
return future;
}
/**
* Submits a task for execution.
*/
@Override
@SuppressWarnings("unchecked")
public Future<?> submit(Runnable command)
{
if (_isShutdown)
throw new IllegalStateException(L.l("Can't submit after ThreadPool has closed"));
TaskFuture future = new TaskFuture(_loader, command, null);
synchronized (_futureSet) {
_futureSet.add(future);
_threadPool.scheduleExecutorTask(future);
}
return future;
}
/**
* Submits a task for execution.
*/
@Override
public <T> Future<T> submit(Runnable task, T result)
{
if (_isShutdown)
throw new IllegalStateException(L.l("Can't submit after ThreadPool has closed"));
TaskFuture<T> future = new TaskFuture<T>(_loader, task, result);
synchronized (_futureSet) {
_futureSet.add(future);
_threadPool.scheduleExecutorTask(future);
}
return future;
}
//
// ScheduledExecutorService
//
/**
* Schedules a future task.
*/
@Override
@SuppressWarnings("unchecked")
public <V> ScheduledFuture<V> schedule(Callable<V> callable,
long delay,
TimeUnit unit)
{
if (_isShutdown)
throw new IllegalStateException(L.l("Can't submit after ThreadPool has closed"));
long initialExpires = Alarm.getCurrentTime() + unit.toMillis(delay);
AlarmFuture future = new AlarmFuture(_loader, callable,
initialExpires, 0, 0);
synchronized (_futureSet) {
_futureSet.add(future);
}
future.queue();
return future;
}
/**
* Schedules a future task.
*/
@Override
@SuppressWarnings("unchecked")
public ScheduledFuture<?> schedule(Runnable command,
long delay,
TimeUnit unit)
{
if (_isShutdown)
throw new IllegalStateException(L.l("Can't submit after ThreadPool has closed"));
long initialExpires = Alarm.getCurrentTime() + unit.toMillis(delay);
AlarmFuture future = new AlarmFuture(_loader, command, initialExpires, 0, 0);
synchronized (_futureSet) {
_futureSet.add(future);
}
future.queue();
return future;
}
/**
* Schedules a future task.
*/
@Override
@SuppressWarnings("unchecked")
public ScheduledFuture<?> scheduleAtFixedRate(Runnable command,
long initialDelay,
long period,
TimeUnit unit)
{
if (_isShutdown)
throw new IllegalStateException(L.l("Can't submit after ThreadPool has closed"));
long initialExpires = Alarm.getExactTime() + unit.toMillis(initialDelay);
AlarmFuture future = new AlarmFuture(_loader, command, initialExpires,
unit.toMillis(period), 0);
synchronized (_futureSet) {
_futureSet.add(future);
}
future.queue();
return future;
}
/**
* Schedules with fixed delay
*/
@Override
@SuppressWarnings("unchecked")
public ScheduledFuture<?> scheduleWithFixedDelay(Runnable command,
long initialDelay,
long delay,
TimeUnit unit)
{
if (_isShutdown)
throw new IllegalStateException(L.l("Can't submit after ThreadPool has closed"));
long initialExpires = Alarm.getCurrentTime() + unit.toMillis(initialDelay);
AlarmFuture future = new AlarmFuture(_loader, command,
initialExpires, 0, unit.toMillis(delay));
synchronized (_futureSet) {
_futureSet.add(future);
}
future.queue();
return future;
}
//
// Timer
//
/**
* Returns the Timer for this pool.
*/
public Timer getTimer()
{
throw new UnsupportedOperationException();
}
//
// lifecycle
//
/**
* Stops the pool on environment shutdown.
*/
@SuppressWarnings("unchecked")
private void stop()
{
_isShutdown = true;
_loader = null;
_threadPool = null;
while (true) {
Future future = null;
synchronized (_futureSet) {
Iterator<Future> iter = _futureSet.iterator();
if (iter.hasNext()) {
future = iter.next();
_futureSet.remove(future);
}
else
break;
}
if (future != null)
future.cancel(true);
}
_futureSet.clear();
}
@SuppressWarnings("unchecked")
void removeFuture(Future future)
{
boolean isFuture;
synchronized (_futureSet) {
isFuture = _futureSet.remove(future);
}
if (isFuture)
future.cancel(true);
}
//
// Environment callbacks.
//
/**
* Called when the environment config phase
*/
@Override
public void environmentConfigure(EnvironmentClassLoader loader)
{
}
/**
* Called when the environment bind phase
*/
@Override
public void environmentBind(EnvironmentClassLoader loader)
{
}
/**
* Called when the environment starts.
*/
@Override
public void environmentStart(EnvironmentClassLoader loader)
{
}
/**
* Called when the environment stops.
*/
@Override
public void environmentStop(EnvironmentClassLoader loader)
{
stop();
}
/**
* Serialize to a webbeans handle
*/
public Object writeReplace()
{
return new SingletonBindingHandle(ScheduledExecutorService.class);
}
@Override
public String toString()
{
if (_loader instanceof EnvironmentClassLoader) {
return (getClass().getSimpleName()
+ "[" + ((EnvironmentClassLoader) _loader).getId() + "]");
}
else
return getClass().getSimpleName() + "[" + _loader + "]";
}
class TaskFuture<T> implements Future<T>, Runnable {
private final ClassLoader _loader;
private final Callable<T> _callable;
private final Runnable _runnable;
private Thread _thread;
private boolean _isCancelled;
private boolean _isDone;
private Exception _exception;
private T _value;
TaskFuture(ClassLoader loader, Callable<T> callable)
{
if (callable == null)
throw new NullPointerException();
_loader = loader;
_callable = callable;
_runnable = null;
}
TaskFuture(ClassLoader loader, Runnable runnable, T result)
{
if (runnable == null)
throw new NullPointerException();
_loader = loader;
_callable = null;
_runnable = runnable;
_value = result;
}
@Override
public boolean isCancelled()
{
return _isCancelled;
}
@Override
public boolean isDone()
{
return _isDone;
}
@Override
public boolean cancel(boolean mayInterrupt)
{
synchronized (this) {
if (_isCancelled || _isDone)
return false;
_isCancelled = true;
removeFuture(this);
notifyAll();
}
Thread thread = _thread;
if (mayInterrupt && thread != null)
thread.interrupt();
return true;
}
@Override
public T get()
throws InterruptedException, ExecutionException
{
try {
return get(Long.MAX_VALUE / 2, TimeUnit.MILLISECONDS);
} catch (TimeoutException e) {
throw new IllegalStateException(e);
}
}
@Override
public T get(long timeout, TimeUnit unit)
throws InterruptedException, ExecutionException, TimeoutException
{
long expire = Alarm.getCurrentTime() + unit.toMillis(timeout);
synchronized (this) {
while (!_isDone && !_isCancelled && Alarm.getCurrentTime() < expire
&& !Thread.currentThread().isInterrupted()) {
if (! Alarm.isTest()) {
long delta = expire - Alarm.getCurrentTime();
if (delta > 0) {
wait(expire - Alarm.getCurrentTime());
}
}
else {
wait(1000);
break;
}
}
}
if (_exception != null)
throw new ExecutionException(_exception);
else if (_isDone)
return _value;
else if (_isCancelled)
throw new CancellationException();
else
throw new TimeoutException();
}
public void run()
{
Thread thread = Thread.currentThread();
_thread = thread;
ClassLoader oldLoader = thread.getContextClassLoader();
try {
if (_isCancelled || _isDone || _isShutdown)
return;
thread.setContextClassLoader(_loader);
if (_callable != null)
_value = _callable.call();
else if (_runnable != null)
_runnable.run();
} catch (RuntimeException e) {
throw e;
} catch (Exception e) {
_exception = e;
} finally {
thread.setContextClassLoader(oldLoader);
_thread = null;
_isDone = true;
ThreadPool threadPool = _threadPool;
if (threadPool != null)
threadPool.completeExecutorTask();
// alarm
removeFuture(this);
synchronized (this) {
notifyAll();
}
}
}
public String toString()
{
Object task = _callable != null ? _callable : _runnable;
if (_isDone)
return "TaskFuture[" + task + ",done]";
else if (_thread != null) {
if (Alarm.isTest())
return "TaskFuture[" + task + ",active]";
else
return "TaskFuture[" + task + "," + _thread + "]";
}
else if (_isCancelled)
return "TaskFuture[" + task + ",cancelled]";
else
return "TaskFuture[" + task + ",pending]";
}
}
class AlarmFuture<T> implements ScheduledFuture<T>, AlarmListener {
private final String _name;
private final ClassLoader _loader;
private final Callable<T> _callable;
private final Runnable _runnable;
private final Alarm _alarm;
private final long _initialExpires;
private final long _period;
private final long _delay;
private long _nextTime;
private Thread _thread;
private boolean _isCancelled;
private boolean _isDone;
private int _alarmCount;
private Exception _exception;
private T _value;
AlarmFuture(ClassLoader loader, Callable<T> callable, long initialExpires,
long period, long delay)
{
_name = "Scheduled[" + callable + "]";
_loader = loader;
_callable = callable;
_runnable = null;
_initialExpires = initialExpires;
_period = period;
_delay = delay;
_nextTime = initialExpires;
_alarm = new Alarm(_name, this, loader);
}
AlarmFuture(ClassLoader loader, Runnable runnable, long initialExpires,
long period, long delay)
{
_name = "Scheduled[" + runnable + "]";
_loader = loader;
_callable = null;
_runnable = runnable;
_initialExpires = initialExpires;
_period = period;
_delay = delay;
_alarm = new Alarm(_name, this, loader);
}
void queue()
{
if (! _isShutdown)
_alarm.queueAt(_initialExpires);
}
@Override
public boolean isCancelled()
{
return _isCancelled;
}
@Override
public boolean isDone()
{
return _isDone;
}
@Override
public long getDelay(TimeUnit unit)
{
long delay = _nextTime - Alarm.getCurrentTime();
return TimeUnit.MILLISECONDS.convert(delay, unit);
}
@Override
public int compareTo(Delayed b)
{
long delta = (getDelay(TimeUnit.MILLISECONDS) - b
.getDelay(TimeUnit.MILLISECONDS));
if (delta < 0)
return -1;
else if (delta > 0)
return 1;
else
return 0;
}
@Override
public boolean cancel(boolean mayInterrupt)
{
synchronized (this) {
if (_isCancelled || _isDone)
return false;
_isCancelled = true;
_alarm.dequeue();
notifyAll();
}
removeFuture(this);
Thread thread = _thread;
if (mayInterrupt && thread != null)
thread.interrupt();
return true;
}
void close()
{
_isDone = true;
_alarm.dequeue();
}
@Override
public T get() throws InterruptedException, ExecutionException
{
try {
return get(Long.MAX_VALUE / 2, TimeUnit.MILLISECONDS);
} catch (TimeoutException e) {
throw new IllegalStateException(e);
}
}
@Override
public T get(long timeout, TimeUnit unit) throws InterruptedException,
ExecutionException, TimeoutException
{
long expire = Alarm.getCurrentTimeActual() + unit.toMillis(timeout);
int count = _alarmCount;
while (!_isDone && !_isCancelled && count == _alarmCount
&& Alarm.getCurrentTimeActual() < expire
&& !Thread.currentThread().isInterrupted()) {
synchronized (this) {
long delta = expire - Alarm.getCurrentTimeActual();
if (delta > 0)
wait(delta);
}
}
if (_exception != null)
throw new ExecutionException(_exception);
else if (_isDone || count != _alarmCount)
return _value;
else if (_isCancelled)
throw new CancellationException();
else
throw new TimeoutException();
}
@Override
public void handleAlarm(Alarm alarm)
{
if (_isCancelled || _isDone || _isShutdown)
return;
_thread = Thread.currentThread();
ClassLoader oldLoader = _thread.getContextClassLoader();
String oldName = _thread.getName();
try {
_thread.setContextClassLoader(_loader);
_thread.setName(_name);
if (_callable != null)
_value = _callable.call();
else
_runnable.run();
} catch (Exception e) {
log.log(Level.FINE, e.toString(), e);
_exception = e;
_isCancelled = true;
} finally {
_thread.setContextClassLoader(oldLoader);
_thread.setName(oldName);
_thread = null;
synchronized (this) {
_alarmCount++;
if (_isCancelled || _isDone || _isShutdown) {
removeFuture(this);
}
else if (_delay > 0) {
_nextTime = Alarm.getCurrentTime() + _delay;
if (! _isShutdown && ! _isDone && ! _isCancelled)
_alarm.queue(_delay);
}
else if (_period > 0) {
long now = Alarm.getCurrentTime();
long next;
do {
next = _initialExpires + _alarmCount * _period;
if (next < now)
_alarmCount++;
} while (next < now);
_alarm.queueAt(next);
}
else {
_isDone = true;
removeFuture(this);
}
notifyAll();
}
}
}
public String toString()
{
Object task = _callable != null ? _callable : _runnable;
if (_isDone)
return "AlarmFuture[" + task + ",done]";
else if (_thread != null) {
if (Alarm.isTest())
return "AlarmFuture[" + task + ",active]";
else
return "AlarmFuture[" + task + "," + _thread + "]";
} else if (_isCancelled)
return "AlarmFuture[" + task + ",cancelled]";
else
return "AlarmFuture[" + task + ",pending]";
}
}
}