将线程添加到线程池后无法获取自定义的线程名称？

public class MyRunnable implements Runnable {
    @Override
    public void run() {
        System.out.println(Thread.currentThread().getName());
    }
}
public class Client {
    public static void main(String[] args) {
        Runnable r = new MyRunnable();
        Thread t = new Thread(r, "Demo");

        ExecutorService service = Executors.newFixedThreadPool(2);
        service.submit(t);
        service.shutdown();
    }
}

输出结果为：
pool-1-thread-1
预期结果为：
Demo