Callable启动线程，它可以有返回值，可以通过future.get()方法来获取线程的执行结果
public static void main(String[] args){
Callable<Integer> callable =
new Callable<Integer>() {
public Integer
call() throws Exception {
return new Random().nextInt(
100);
}
};
FutureTask<Integer> future =
new FutureTask<Integer>(callable);
new Thread(future).start();
try {
Thread.sleep(
1000);
System.
out.println(future.
get());
}
catch (InterruptedException e) {
e.printStackTrace();
}
catch (ExecutionException e) {
e.printStackTrace();
}
}
