并发：Callabel 接口

 1 public class TaskWithResult implements Callable<String> {
 2 
 3     private int id;
 4 
 5     public TaskWithResult(int id) {
 6         this.id=id;
 7     }
 8 
 9     @Override
10     public String call() throws Exception {
11         // TODO Auto-generated method stub
12         return "result of TaskWithResult:" + id;
13     }
14 
15 }

 1 public class CallableDemo {
 2     public static void main(String[] args) {
 3         // TODO Auto-generated method stub
 4         ExecutorService exec = Executors.newCachedThreadPool();
 5         ArrayList<Future<String>> results = new ArrayList<Future<String>>();
 6         for (int i = 0; i < 10; i++)
 7             results.add(exec.submit(new TaskWithResult(i)));
 8         for (Future<String> fs : results)
 9             try {
10                 System.out.println(fs.get());
11             } catch (InterruptedException e) {
12                 // TODO Auto-generated catch block
13                 e.printStackTrace();
14             } catch (ExecutionException e) {
15                 // TODO Auto-generated catch block
16                 e.printStackTrace();
17             }finally{
18                 exec.shutdown();
19             }
20     }
21 }