java多线程返回值使用示例(callable与futuretask)

import java.io.FileNotFoundException;
import java.io.IOException;
import java.util.concurrent.Callable;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.FutureTask;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.TimeoutException;

public class MyTest {

 // 接收在run方法中捕获的异常，然后自定义方法抛出异常
    //private static Throwable exception;
 /**
  * @param args
  */
 public static void main(String[] args) {
  // TODO Auto-generated method stub
  String result = "";
  ExecutorService executor = Executors.newSingleThreadExecutor(); 
  FutureTask<String> future = 
         new FutureTask<String>(new Callable<String>() {//使用Callable接口作为构造参数 
           public String call() { 
             //真正的任务在这里执行，这里的返回值类型为String，可以为任意类型
            try {
      Thread.sleep(10000);
     } catch (InterruptedException e) {
      // TODO Auto-generated catch block
      //exception = e;
      //e.printStackTrace();
     }
           return "11111";
         }}); 
  executor.execute(future); 
  //在这里可以做别的任何事情 
  try { 
      result = future.get(5000, TimeUnit.MILLISECONDS); //取得结果，同时设置超时执行时间为5秒。同样可以用future.get()，不设置执行超时时间取得结果 
  } catch (InterruptedException e) {
   //System.out.println("任务已经取消");
   future.cancel(true); 
  } catch (ExecutionException e) { 
   future.cancel(true); 
  } catch (TimeoutException e) { 
   future.cancel(true); 
  } finally { 
      executor.shutdown(); 
  } 
  System.out.println("result:"+result);
 }

 /* public void throwException() throws FileNotFoundException, IOException {
         if (exception instanceof FileNotFoundException)
             throw (FileNotFoundException) exception;
         if (exception instanceof IOException)
             throw (IOException) exception;
     }*/

}