控制程序运行时间或外部接口调用超时时间
? 经常在运行一个新线程或调用第三方接口时存在一个问题，即线程在预计的时间内没有成功结束而导致程序失控。调用第三方系统，因为网络超时或对方响应速度异常导致己方系统异常的问题在开发中时常遇到。通过下面代码旨在解决类似问题。使用到的相关api暂未深入研究原理，待有时间补上。
?
import java.util.Calendar;import java.util.concurrent.ExecutorService;import java.util.concurrent.Executors;import java.util.concurrent.Future;import java.util.concurrent.ThreadFactory;import java.util.concurrent.TimeUnit;public class TestCallable {private static ExecutorService executor=Executors.newCachedThreadPool(new ThreadFactory() {int ncount=0;@Overridepublic Thread newThread(Runnable r) {ncount++;Thread invokeThread=new Thread(r);invokeThread.setName("Invoker-thread-"+ncount);invokeThread.setDaemon(true);return invokeThread;}});public static void callSth(Runnable task,TimeUnit unit,long timeout)throws Exception{Future<?> futureResult=executor.submit(task);futureResult.get(timeout, unit);}public static void main(String[] args) {System.out.println(1<<2);Runnable rb=new Runnable() {@Overridepublic void run() {TestCallable tc=new TestCallable();tc.dosth();//模拟调用外部接口}};//5秒超时try {long s=Calendar.getInstance().getTimeInMillis();callSth(rb,TimeUnit.MILLISECONDS,5000);System.out.println("运行时间:"+(Calendar.getInstance().getTimeInMillis()-s));} catch (Exception e) {//抓这两个异常更准确，纯粹模拟为省事就抓老大了。InterruptedException, TimeoutException System.err.println("调用外部接口超时了!");}//模拟2秒超时try {callSth(rb,TimeUnit.MILLISECONDS,2000);} catch (Exception e) {//抓这两个异常更准确，纯粹模拟为省事就抓老大了。InterruptedException, TimeoutException System.err.println("调用外部接口超时了!");}}public void dosth(){//模拟外部接口try {System.out.println("开始睡觉");Thread.sleep(2500);System.out.println("睡醒了");} catch (InterruptedException e) {// TODO Auto-generated catch blocke.printStackTrace();}}} ??
?
?