/*
* Copyright 2002-2012 the original author or authors.
*
* Licensed 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.springframework.scheduling.commonj;
import java.util.Date;
import java.util.concurrent.Delayed;
import java.util.concurrent.FutureTask;
import java.util.concurrent.ScheduledFuture;
import java.util.concurrent.TimeUnit;
import commonj.timers.Timer;
import commonj.timers.TimerListener;
import org.springframework.scheduling.TaskScheduler;
import org.springframework.scheduling.Trigger;
import org.springframework.scheduling.support.SimpleTriggerContext;
import org.springframework.scheduling.support.TaskUtils;
import org.springframework.util.ErrorHandler;
/**
* Implementation of Spring's {@link TaskScheduler} interface, wrapping
* a CommonJ {@link commonj.timers.TimerManager}.
*
* @author Juergen Hoeller
* @author Mark Fisher
* @since 3.0
*/
public class TimerManagerTaskScheduler extends TimerManagerAccessor implements TaskScheduler {
private volatile ErrorHandler errorHandler;
/**
* Provide an {@link ErrorHandler} strategy.
*/
public void setErrorHandler(ErrorHandler errorHandler) {
this.errorHandler = errorHandler;
}
@Override
public ScheduledFuture<?> schedule(Runnable task, Trigger trigger) {
return new ReschedulingTimerListener(errorHandlingTask(task, true), trigger).schedule();
}
@Override
public ScheduledFuture<?> schedule(Runnable task, Date startTime) {
TimerScheduledFuture futureTask = new TimerScheduledFuture(errorHandlingTask(task, false));
Timer timer = getTimerManager().schedule(futureTask, startTime);
futureTask.setTimer(timer);
return futureTask;
}
@Override
public ScheduledFuture<?> scheduleAtFixedRate(Runnable task, Date startTime, long period) {
TimerScheduledFuture futureTask = new TimerScheduledFuture(errorHandlingTask(task, true));
Timer timer = getTimerManager().scheduleAtFixedRate(futureTask, startTime, period);
futureTask.setTimer(timer);
return futureTask;
}
@Override
public ScheduledFuture<?> scheduleAtFixedRate(Runnable task, long period) {
TimerScheduledFuture futureTask = new TimerScheduledFuture(errorHandlingTask(task, true));
Timer timer = getTimerManager().scheduleAtFixedRate(futureTask, 0, period);
futureTask.setTimer(timer);
return futureTask;
}
@Override
public ScheduledFuture<?> scheduleWithFixedDelay(Runnable task, Date startTime, long delay) {
TimerScheduledFuture futureTask = new TimerScheduledFuture(errorHandlingTask(task, true));
Timer timer = getTimerManager().schedule(futureTask, startTime, delay);
futureTask.setTimer(timer);
return futureTask;
}
@Override
public ScheduledFuture<?> scheduleWithFixedDelay(Runnable task, long delay) {
TimerScheduledFuture futureTask = new TimerScheduledFuture(errorHandlingTask(task, true));
Timer timer = getTimerManager().schedule(futureTask, 0, delay);
futureTask.setTimer(timer);
return futureTask;
}
private Runnable errorHandlingTask(Runnable delegate, boolean isRepeatingTask) {
return TaskUtils.decorateTaskWithErrorHandler(delegate, this.errorHandler, isRepeatingTask);
}
/**
* ScheduledFuture adapter that wraps a CommonJ Timer.
*/
private static class TimerScheduledFuture extends FutureTask<Object> implements TimerListener, ScheduledFuture<Object> {
protected transient Timer timer;
protected transient boolean cancelled = false;
public TimerScheduledFuture(Runnable runnable) {
super(runnable, null);
}
public void setTimer(Timer timer) {
this.timer = timer;
}
@Override
public void timerExpired(Timer timer) {
runAndReset();
}
@Override
public boolean cancel(boolean mayInterruptIfRunning) {
boolean result = super.cancel(mayInterruptIfRunning);
this.timer.cancel();
this.cancelled = true;
return result;
}
@Override
public long getDelay(TimeUnit unit) {
return unit.convert(System.currentTimeMillis() - this.timer.getScheduledExecutionTime(), TimeUnit.MILLISECONDS);
}
@Override
public int compareTo(Delayed other) {
if (this == other) {
return 0;
}
long diff = getDelay(TimeUnit.MILLISECONDS) - other.getDelay(TimeUnit.MILLISECONDS);
return (diff == 0 ? 0 : ((diff < 0)? -1 : 1));
}
}
/**
* ScheduledFuture adapter for trigger-based rescheduling.
*/
private class ReschedulingTimerListener extends TimerScheduledFuture {
private final Trigger trigger;
private final SimpleTriggerContext triggerContext = new SimpleTriggerContext();
private volatile Date scheduledExecutionTime;
public ReschedulingTimerListener(Runnable runnable, Trigger trigger) {
super(runnable);
this.trigger = trigger;
}
public ScheduledFuture<?> schedule() {
this.scheduledExecutionTime = this.trigger.nextExecutionTime(this.triggerContext);
if (this.scheduledExecutionTime == null) {
return null;
}
setTimer(getTimerManager().schedule(this, this.scheduledExecutionTime));
return this;
}
@Override
public void timerExpired(Timer timer) {
Date actualExecutionTime = new Date();
super.timerExpired(timer);
Date completionTime = new Date();
this.triggerContext.update(this.scheduledExecutionTime, actualExecutionTime, completionTime);
if (!this.cancelled) {
schedule();
}
}
}
}