package wzh.test; import java.util.ArrayList; import java.util.concurrent.Callable; import java.util.concurrent.ExecutorService; import java.util.concurrent.Executors; import java.util.concurrent.Future; class TaskWithResult implements Callable<String>{ private int id; public TaskWithResult(int id){ this.id=id; } @Override public String call() throws Exception { return "result of TaskWithResult "+id; } } public class CallableDemo { public static void main(String[] args) { ExecutorService exec=Executors.newCachedThreadPool(); ArrayList<Future<String>> results=new ArrayList<Future<String>>(); for (int i = 0; i < 10; i++) { results.add(exec.submit(new TaskWithResult(i))); } for (Future<String> future : results) { try { System.out.println(future.get()); } catch (Exception e) { e.printStackTrace(); } finally{ exec.shutdown(); } } } }