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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();

 

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。

 

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。

 

/*
 * Copyright 2005 OpenSymphony
 *
 * 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();
    }

}

 

 

 

   需要源码的可以去这里下载 http://dl.dbank.com/c0a4wn14yl