外部クラスから JPanel の幅と高さにアクセスするにはどうすればよいですか?

public class GamePanel extends JPanel implements Runnable{
    // ... (same as before)

    public void move() {
        for(Rect rect: rect) {
            rect.move(this); // Passing 'this' reference to the 'move()' method
        }
    }
}

public class Rect {
    // ... (same as before)

    public void move(JPanel panel){
        // Now you can access the JPanel's width and height using 'panel'
        int jpWidth = panel.getWidth();
        int jpHeight = panel.getHeight();
        
        // ... (remaining code)
    }
}