/*
* Copyright 2002-2009 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.timer;
import java.util.Timer;
import java.util.concurrent.Callable;
import java.util.concurrent.Future;
import java.util.concurrent.FutureTask;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.beans.factory.BeanNameAware;
import org.springframework.beans.factory.DisposableBean;
import org.springframework.beans.factory.InitializingBean;
import org.springframework.scheduling.SchedulingTaskExecutor;
import org.springframework.util.Assert;
import org.springframework.util.StringUtils;
/**
* {@link org.springframework.core.task.TaskExecutor} implementation that uses a
* single {@link Timer} for executing all tasks, effectively resulting in
* serialized asynchronous execution on a single thread.
*
* @author Juergen Hoeller
* @since 2.0
* @see java.util.Timer
* @deprecated as of Spring 3.0, in favor of the <code>scheduling.concurrent</code>
* package which is based on Java 5's <code>java.util.concurrent.ExecutorService</code>
*/
@Deprecated
public class TimerTaskExecutor implements SchedulingTaskExecutor, BeanNameAware, InitializingBean, DisposableBean {
protected final Log logger = LogFactory.getLog(getClass());
private Timer timer;
private long delay = 0;
private String beanName;
private boolean timerInternal = false;
/**
* Create a new TimerTaskExecutor that needs to be further configured and initialized.
* @see #setTimer
* @see #afterPropertiesSet
*/
public TimerTaskExecutor() {
}
/**
* Create a new TimerTaskExecutor for the given {@link Timer}.
* @param timer the {@link Timer} to wrap
*/
public TimerTaskExecutor(Timer timer) {
Assert.notNull(timer, "Timer must not be null");
this.timer = timer;
}
/**
* Set the {@link Timer} to use for this {@link TimerTaskExecutor}, for example
* a shared {@link Timer} instance defined by a {@link TimerFactoryBean}.
* <p>If not specified, a default internal {@link Timer} instance will be used.
* @param timer the {@link Timer} to use for this {@link TimerTaskExecutor}
* @see TimerFactoryBean
*/
public void setTimer(Timer timer) {
this.timer = timer;
}
/**
* Set the delay to use for scheduling tasks passed into the plain
* {@link #execute(Runnable)} method. Default is 0.
* <p>Note that calls to {@link #execute(Runnable, long)} will use the
* given timeout as delay if it is lower than the general delay.
* @param delay the delay in milliseconds before the task is to be executed
*/
public void setDelay(long delay) {
this.delay = delay;
}
public void setBeanName(String beanName) {
this.beanName = beanName;
}
public void afterPropertiesSet() {
if (this.timer == null) {
logger.info("Initializing Timer");
this.timer = createTimer();
this.timerInternal = true;
}
}
/**
* Create a new {@link Timer} instance. Called by <code>afterPropertiesSet</code>
* if no {@link Timer} has been specified explicitly.
* <p>The default implementation creates a plain non-daemon {@link Timer}.
* If overridden, subclasses must take care to ensure that a non-null
* {@link Timer} is returned from the execution of this method.
* @see #afterPropertiesSet
* @see java.util.Timer#Timer(String, boolean)
*/
protected Timer createTimer() {
if (StringUtils.hasText(this.beanName)) {
return new Timer(this.beanName);
}
else {
return new Timer();
}
}
/**
* Return the underlying Timer behind this TimerTaskExecutor.
*/
protected final Timer getTimer() {
Assert.notNull(this.timer, "Timer not initialized yet");
return this.timer;
}
/**
* Schedules the given {@link Runnable} on this executor's {@link Timer} instance,
* wrapping it in a {@link DelegatingTimerTask}.
* @param task the task to be executed
*/
public void execute(Runnable task) {
getTimer().schedule(new DelegatingTimerTask(task), this.delay);
}
public void execute(Runnable task, long startTimeout) {
long actualDelay = (startTimeout < this.delay ? startTimeout : this.delay);
getTimer().schedule(new DelegatingTimerTask(task), actualDelay);
}
public Future<?> submit(Runnable task) {
FutureTask<Object> future = new FutureTask<Object>(task, null);
execute(future);
return future;
}
public <T> Future<T> submit(Callable<T> task) {
FutureTask<T> future = new FutureTask<T>(task);
execute(future);
return future;
}
/**
* This task executor prefers short-lived work units.
*/
public boolean prefersShortLivedTasks() {
return true;
}
/**
* Cancel the {@link Timer} on bean factory shutdown, stopping all scheduled tasks.
* @see java.util.Timer#cancel()
*/
public void destroy() {
if (this.timerInternal) {
logger.info("Cancelling Timer");
this.timer.cancel();
}
}
}
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