(一)java代碼中定時(shí)調(diào)用的三種方法:
方法一:使用thread創(chuàng)建一個(gè)thread,然后讓它在while循環(huán)里一直運(yùn)行著,通過(guò)sleep方法來(lái)達(dá)到定時(shí)任務(wù)的效果。代碼如下:
public static void main(String[] args) { final long timeInterval = 1000; Runnable runnable = new Runnable() { public void run() { while (true) { System.out.PRintln("方法一:循環(huán)調(diào)用 !! 時(shí)間=" + new Date() ); try { Thread.sleep(timeInterval); } catch (InterruptedException e) { e.printStackTrace(); } } } }; Thread thread = new Thread(runnable); thread.start(); }方法二:在實(shí)現(xiàn)時(shí),Timer類可以調(diào)度任務(wù),TimerTask則是通過(guò)在run()方法里實(shí)現(xiàn)具體任務(wù)。 Timer實(shí)例可以調(diào)度多任務(wù),它是線程安全的。當(dāng)Timer的構(gòu)造器被調(diào)用時(shí),它創(chuàng)建了一個(gè)線程,這個(gè)線程可以用來(lái)調(diào)度任務(wù)。
詳解Timer地址,可查看調(diào)用時(shí)間 http://blog.csdn.net/chenssy/article/details/32703499
下面是簡(jiǎn)單代碼:
public static void main(String[] args) { TimerTask task = new TimerTask() { @Override public void run() { System.out.println("方法二:Timer定時(shí)調(diào)用 !!! 時(shí)間=" + new Date() ); } }; Timer timer = new Timer(); long delay = 10000; long intevalPeriod = 1 * 1000; timer.scheduleAtFixedRate(task, delay, intevalPeriod); }方法三:ScheduledExecutorService是從Java SE5的java.util.concurrent里,做為并發(fā)工具類被引進(jìn)的,這是最理想的定時(shí)任務(wù)實(shí)現(xiàn)方式。下面是簡(jiǎn)單代碼:public static void main(String[] args) { Runnable runnable = new Runnable() { public void run() { System.out.println("方法三:ScheduledExecutorService定時(shí)調(diào)用 !! 時(shí)間=" + new Date() ); } }; ScheduledExecutorService service = Executors.newSingleThreadScheduledExecutor(); // 第二個(gè)參數(shù)為首次執(zhí)行的延時(shí)時(shí)間,第三個(gè)參數(shù)為定時(shí)執(zhí)行的間隔時(shí)間 service.scheduleAtFixedRate(runnable, 5, 3, TimeUnit.SECONDS); }(二)java代碼定時(shí)調(diào)用在spring中的例子:(下面代碼為固定幾分鐘調(diào)用一次,百度文庫(kù)定時(shí)調(diào)用http://wenku.baidu.com/view/a8ac2b71a8114431b80dd809.html)
編寫類TimerManager:
public class TimerManager { public TimerManager() { NFDFlightDataTimerTask task = new NFDFlightDataTimerTask(); ScheduledExecutorService service = Executors.newSingleThreadScheduledExecutor(); // 第二個(gè)參數(shù)為首次執(zhí)行的延時(shí)時(shí)間,第三個(gè)參數(shù)為定時(shí)執(zhí)行的間隔時(shí)間 service.scheduleAtFixedRate(task, 5, 3, TimeUnit.SECONDS); }}編寫類NFDFlightDataTaskListener:
public class NFDFlightDataTimerTask extends TimerTask{ private static Logger log = Logger.getLogger(NFDFlightDataTimerTask.class); @Override public void run() { try { //在這里寫你要執(zhí)行的內(nèi)容 System.out.println("執(zhí)行定時(shí)調(diào)用 !! 時(shí)間=" + new Date() ); } catch (Exception e) { log.info("-------------解析信息發(fā)生異常--------------"); } }}編寫類NFDFlightDataTaskListener:
public class NFDFlightDataTaskListener implements ServletContextListener { public void contextInitialized(ServletContextEvent event) { new TimerManager(); } public void contextDestroyed(ServletContextEvent event) { }}然后要在web.xml里面配置監(jiān)聽器:
<listener> <listener-class>com.cxy.timer.NFDFlightDataTaskListener</listener-class> </listener>希望對(duì)你有幫助,祝你有一個(gè)好心情,加油!
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