java如何使用ExecuterService以线程的形式逐个运行两个方法

Question

我试图执行两个方法，其中两个方法将在一段时间后逐个执行，我使用ExecuterService。我已经实现了部分代码，但完整的功能我无法实现，直到现在，我在这里发布我的代码

public class ExampleExecuterService {

private static final int MYTHREADS = 3000;
public static void main(String[] args) throws Exception {

    ExecutorService executor = Executors.newFixedThreadPool(MYTHREADS);

    Object methodList[]={

            aMethod(),bMethod()
    };


    for(int i=0;i<methodList.length;i++){
        Object myList = methodList[i];
        Runnable worker = new MyRunnable(myList);
        executor.execute(worker);
    }
    executor.shutdown();
    // Wait until all threads are finish
            while (!executor.isTerminated()) {

            }
  System.out.println("\nFinished all threads");

}

public static class MyRunnable implements Runnable {

    private Object myList=null;

    MyRunnable(Object myList) {
        this.myList = myList;
    }
    @Override
    public void run() {


        try{

            myList.wait(2000);
        }catch(Exception e){
            e.printStackTrace();
        }
    }


}

private static Object bMethod() {
    System.out.println("This is inside method a ");
    return null;
}
private static Object aMethod() {

    System.out.println("This is inside method b ");
    return null;
}

}

我想要aMethod()和bMethod()在20秒后运行，最后executer将停止。如何使用我的代码实现这一点。谁来帮帮我