spring的Scheduled(定时任务)和多线程

一、前言

      在我们日常的开发中,经常用到数据同步的更新,这时我们采用的是spring的定时任务和java的多线程进行数据的更新,进行时实的服务调用。

二.实现思路

           1.创建线程类

           2.创建ExecutorService线程连接池

           3.调用线程池操作

           4.spring的Scheduled(定时任务)配置 

三.创建线程类

     创建的线程类,我们采用的是实现Runnable接口,使用该类可以共享,在线程中要么继承Thread,或者实现Runnable接口,其中Thread是实现了Runnable的接口,实现Runnable接口可以更好的扩展和共享类,因为java是单继承多实现的程序。

public class ArchiveTask implements Runnable {
     
    /**
     * log.
     */
    private static Logger logger = LoggerFactory.getLogger(ArchiveTask.class);
     
    //注:由于spring事务配置采用的注解的方式来配置传播性配置,此类没有在spring传播配置里面,所以不能用自动装配的方式来配置
    private static FaxRecvArchiveCtrl faxRecvArchiveCtrl = AppContextAware.getBean(FaxRecvArchiveCtrl.class);
 
    private FaxRecvArchiveDTO faxRecvArchiveDTO;
     
    /**
     *  CountDownLatch是一个同步辅助类,在一组线程在执行操作之前,允许一个或多线程处于等待
     *  主要方法
     *          public CountDownLatch(int count);
     *          public void countDown();
     *          public void await() throws InterruptedException
     *
     *          构造方法参数指定了计数的次数
     *          countDown方法,当前线程调用此方法,则计数减一
     *          awaint方法,调用此方法会一直阻塞当前线程,直到计时器的值为0
     * 
     */ 
    private CountDownLatch latch;
     
      
    public ArchiveTask(FaxRecvArchiveDTO faxRecvArchiveDTO, CountDownLatch latch) {
        this.faxRecvArchiveDTO = faxRecvArchiveDTO;
        this.latch = latch;
    }
 
    @Override
    public void run() {
        try {
            faxRecvArchiveCtrl.updateArchiveFileFlag(ServiceFactory.getCurrentSessionId(), faxRecvArchiveDTO);
        } catch (Exception ex) {
            logger.debug("["+this.faxRecvArchiveDTO.getFaxKey()+"]线程执行异常,错误信息为:"+ex.getMessage());
        } finally{
            logger.debug("线程执行完:"+this.faxRecvArchiveDTO.getFaxKey());
            latch.countDown();
        }
    }
}

 四、调用线程池操作

public class EasyFaxArchiveFileMgr {
	/**
	 * 日志
	 */
	Logger logger = LoggerFactory.getLogger(EasyFaxArchiveFileMgr.class);

	/**
	 * 线程池数量
	 */
	private int ThreadNum = 5;
	
	
	private static FaxRecvArchiveCtrl faxRecvArchiveCtrl = AppContextAware.getBean(FaxRecvArchiveCtrl.class);
	
	private static List<FaxRecvArchiveDTO> noArchiveList = new ArrayList<FaxRecvArchiveDTO>();

public void archiveFile() throws ShineException{ noArchiveList = faxRecvArchiveCtrl.getFaxRecvNoArchiveFile(); ExecutorService executorService = Executors.newFixedThreadPool(ThreadNum); List<ArchiveTask> taskList = new ArrayList<ArchiveTask>(); synchronized (noArchiveList) { while(CollectionUtils.isEmpty(noArchiveList) == false) { try { //定义计数器 int countLatch = (noArchiveList.size() > ThreadNum) ? ThreadNum :noArchiveList.size(); CountDownLatch latch = new CountDownLatch(countLatch); //组织任务 for(int i = 0; i < ThreadNum; i++){ if(CollectionUtils.isEmpty(noArchiveList) == false) { taskList.add(new ArchiveTask(noArchiveList.remove(0),latch)); }else{ break; } } //提交任务 if (CollectionUtils.isEmpty(taskList) == false) { for (int i = 0, size = taskList.size(); i < size; i++) { executorService.submit(taskList.get(i)); } }//等待所有线程都执行完 latch.await(); } catch(Exception ex) { logger.error("线程池处理出错,原因:"+ex.getMessage()); } finally { taskList.clear(); }
//关闭线程连接池 executorService.shutdown(); } } } }

五.spring配置

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xmlns:context="http://www.springframework.org/schema/context"
    xsi:schemaLocation="http://www.springframework.org/schema/beans 
           http://www.springframework.org/schema/beans/spring-beans-2.5.xsd
           http://www.springframework.org/schema/context
           http://www.springframework.org/schema/context/spring-context-2.5.xsd">
	
	<bean >
        <property name="scheduledTimerTasks">
            <list>
                <ref bean="archiveFileScheduler"/>
            </list>
        </property>
    </bean>
<bean > <property name="delay"> <!-- 启动30秒后开始运行 --> <value>30000</value> </property> <property name="period"> <!-- 每10秒运行 --> <value>10000</value> </property> <property name="timerTask"> <ref bean="archiveFileHandleMethodInvoker" /> </property> </bean> <bean > <property name="targetObject"> <ref bean="com.shine.emofs.thirdparty.easyfax.ctrl.EasyFaxArchiveFileMgr" /> </property> <property name="targetMethod"> <value>archiveFile</value> </property> </bean> </beans>

六、参考:

  ExecutorService线程连接池:http://www.itzhai.com/the-executorservice-common-method-newfixedthreadpool-of-create-fixed-size-thread-pool.html#read-more