import java.util.concurrent.Callable;import java.util.concurrent.ExecutionException;import java.util.concurrent.ExecutorService;import java.util.concurrent.Executors;import java.util.concurrent.Future;import java.util.concurrent.TimeUnit;import java.util.concurrent.TimeoutException;public class FutureTest{  public static void main(String[] args) throws InterruptedException,    ExecutionException, TimeoutException  {    final ExecutorService exec = Executors.newFixedThreadPool(1);        Callable<String> call = new Callable<String>() {      public String call() throws InterruptedException      {        // 開始執(zhí)行耗時操作          Thread.sleep(1000 * 2);         return "1線程執(zhí)行完成.";      }    };    Callable<String> call2 = new Callable<String>() {      public String call() throws Exception      {        // 開始執(zhí)行耗時操作        // Thread.sleep(1000 * 5);        return "2線程執(zhí)行完成.";      }    };        Callable<String> call3 = new Callable<String>() {      public String call() throws Exception      {        // 開始執(zhí)行耗時操作        // Thread.sleep(1000 * 5);        return "3線程執(zhí)行完成.";      }    };    Future<String> future = exec.submit(call);    Future<String> future3 = exec.submit(call3);     Future<String> future2 = exec.submit(call2);      String obj="";      String obj2 ="";      String obj3 ="";      try{       obj = future.get(500, TimeUnit.MILLISECONDS); // 任務(wù)處理超時時間設(shè)為      }// 1 秒      catch(Exception e){        System.out.println("處理超時啦....");        e.printStackTrace();      }            try{        obj3 = future3.get(3000, TimeUnit.MILLISECONDS); // 任務(wù)處理超時時間設(shè)為        }// 1 秒        catch(Exception e){          System.out.println("處理超時啦....");          e.printStackTrace();        }            try{       obj2 = future2.get(3000, TimeUnit.MILLISECONDS);}      catch(Exception e){        System.out.println("處理超時啦....");        e.printStackTrace();      }      System.out.println("3任務(wù)成功返回:" + obj3);      System.out.println("2任務(wù)成功返回:" + obj2);      System.out.println("1任務(wù)成功返回:" + obj);      exec.shutdown();    } }