子类方法不会覆盖父级中相同签名的方法

Question

Why is my child class method not overriding the method of the same signature in its parent class?

Summary:

I have a class PlayerPaddle that extends an abstract class Paddle , which extends the abstract class Actor (the context here is a pong game). Paddle and PlayerPaddle both have a method with the same signature:

public void moveDown()

The intention is to have the PlayerPaddle moveDown method override that of Paddle . The problem here is when I call this.moveDown() inside PlayerPaddle , only the moveDown method of Paddle is called.

The details:

Breakpoints set on moveDown() in Paddle are tripped, while breakpoints on moveDown() in PlayerPaddle never trip. I also tried @Override on the PlayerPaddle moveDown method, but it still calls the Paddle moveDown method.

The context:

The goal is for PlayerPaddle objects to move up/down at a different speed than other Paddle objects. So the same problem occurs for the moveUp method as well.

Code below:

abstract public class Actor {
    public void releasedEvent(KeyEvent e) {
    }
}

abstract public class Paddle extends Actor {
     public void moveDown() { // this method is called
          body.setVel(0, Game.dX / 10.);   
     }
}


public class PlayerPaddle extends Paddle {
    @Override
    public void moveDown() { // this method never gets called
       body.setVel(0,  Game.dX );
    } 

    public void receiveEvent(KeyEvent e) {
       if (e.getKeyCode() == KeyEvent.VK_UP) {
          this.moveUp(); 
       } else if (e.getKeyCode() == KeyEvent.VK_DOWN) {
          this.moveDown(); // Want to call moveDown() inside PlayerPaddle
       }
    }

}

I am happy to provide clarification.

Answer 1

See the simple case, it works:

public class Test{

  public static void main(String args[])
  {     
    new PlayerPaddle().receiveEvent();
  }
}
abstract class Actor {
  public void releasedEvent(KeyEvent e) {
  }
}
abstract class Paddle extends Actor {
  public void moveDown() { // this method is called
      System.out.println("paddle");
  }
}
class PlayerPaddle extends Paddle {
  @Override
  public void moveDown() { // this method never gets called
   System.out.println("playerpaddle");
  } 
  public void receiveEvent() {
     this.moveDown(); // Want to call moveDown() inside PlayerPaddle      
  }
}

It calls the PlayerPaddle one.