java 几种常见的定时器

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今天闲着没事就总结了一下在java中常用的几种定时器。

主要有3种java.util.Timer， ScheduledExecutorService和quartz

一.Timer

举个简单例子。每隔5秒自动刷新。

Timer timerFresh = new Timer();
timerFresh.schedule(new TimerTask() {
public void run() {
Display.getDefault().syncExec(new Runnable() {
public void run() {
setInputValue();//这里写你的方法，就可以了。
}
});
}
}, 5000, 5000);

二.ScheduledExecutorService

ScheduledExecutorService
schedule(Runnablecommand, long delay, TimeUnitunit) : ScheduledFuture
schedule(Callable<V> callable, long delay, TimeUnitunit) : ScheduledFuture
scheduleAtFixedRate(Runnablecomand, long initDelay, long period, TimeUnitunit) : ScheduledFuture
scheduleWithFixedDelay(Runnablecommand, long initDelay, long delay, TimeUnitunit) :

ScheduledFuturejava.util.concurrent.Executors是ScheduledExecutorService的工厂类，通过Executors，你可以创建你所需要的ScheduledExecutorService。JDK 1.5之后有了ScheduledExecutorService，不建议你再使用java.util.Timer，因为它无论功能性能都不如ScheduledExecutorService。
ScheduledExecutorService
ScheduledTaskSubmitter
ScheduleFuture<Object> future = scheduler.schedule(task, 1, TimeUnit.SECONDS);
// 等待到任务被执行完毕返回结果
// 如果任务执行出错，这里会抛ExecutionException
future.get();
//取消调度任务
future.cancel();

比如这篇文章讲的很好。

在Timer和ScheduledExecutorService间决择

http://sunnylocus.javaeye.com/blog/530969

三.quartz

这个目前考虑的比较全面用的比较多。

/*
*
* 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.quartz.examples.example4;
import java.util.Date;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.quartz.JobDetail;
import org.quartz.Scheduler;
import org.quartz.SchedulerFactory;
import org.quartz.SchedulerMetaData;
import org.quartz.SimpleTrigger;
import org.quartz.TriggerUtils;
import org.quartz.impl.StdSchedulerFactory;
/**
* This Example will demonstrate how job parameters can be
* passed into jobs and how state can be maintained
*
* @author Bill Kratzer
*/
public class JobStateExample {
public void run() throws Exception {
Log log = LogFactory.getLog(JobStateExample.class);
log.info("------- Initializing -------------------");
// First we must get a reference to a scheduler
SchedulerFactory sf = new StdSchedulerFactory();
Scheduler sched = sf.getScheduler();
log.info("------- Initialization Complete --------");
log.info("------- Scheduling Jobs ----------------");
// get a "nice round" time a few seconds in the future....
long ts = TriggerUtils.getNextGivenSecondDate(null, 10).getTime();
// job1 will only run 5 times, every 10 seconds
JobDetail job1 = new JobDetail("job1", "group1", ColorJob.class);
SimpleTrigger trigger1 = new SimpleTrigger("trigger1", "group1", "job1", "group1",
new Date(ts), null, 4, 10000);
// pass initialization parameters into the job
job1.getJobDataMap().put(ColorJob.FAVORITE_COLOR, "Green");
job1.getJobDataMap().put(ColorJob.EXECUTION_COUNT, 1);
// schedule the job to run
Date scheduleTime1 = sched.scheduleJob(job1, trigger1);
log.info(job1.getFullName() +
" will run at: " + scheduleTime1 +
" and repeat: " + trigger1.getRepeatCount() +
" times, every " + trigger1.getRepeatInterval() / 1000 + " seconds");
// job2 will also run 5 times, every 10 seconds
JobDetail job2 = new JobDetail("job2", "group1", ColorJob.class);
SimpleTrigger trigger2 = new SimpleTrigger("trigger2", "group1", "job2", "group1",
new Date(ts + 1000), null, 4, 10000);
// pass initialization parameters into the job
// this job has a different favorite color!
job2.getJobDataMap().put(ColorJob.FAVORITE_COLOR, "Red");
job2.getJobDataMap().put(ColorJob.EXECUTION_COUNT, 1);
// schedule the job to run
Date scheduleTime2 = sched.scheduleJob(job2, trigger2);
log.info(job2.getFullName() +
" will run at: " + scheduleTime2 +
" and repeat: " + trigger2.getRepeatCount() +
" times, every " + trigger2.getRepeatInterval() / 1000 + " seconds");
log.info("------- Starting Scheduler ----------------");
// All of the jobs have been added to the scheduler, but none of the jobs
// will run until the scheduler has been started
sched.start();
log.info("------- Started Scheduler -----------------");
log.info("------- Waiting 60 seconds... -------------");
try {
// wait five minutes to show jobs
Thread.sleep(60L * 1000L);
// executing...
} catch (Exception e) {
}
log.info("------- Shutting Down ---------------------");
sched.shutdown(true);
log.info("------- Shutdown Complete -----------------");
SchedulerMetaData metaData = sched.getMetaData();
log.info("Executed " + metaData.numJobsExecuted() + " jobs.");
}
public static void main(String[] args) throws Exception {
JobStateExample example = new JobStateExample();
example.run();
}
}