如何使用键绑定代替KeyListener？

Question

我目前正在编写一个游戏，其中两个对象根据键盘输入在一个窗口中移动。一个对象使用ASDW键移动，另一个对象使用箭头键移动。我目前正在使用KeyListener来执行此操作，但是KeyListener不能与同时输入一起使用，因此两个对象不能同时移动。我知道使用键绑定可以同时进行输入，但是我不知道如何实际使用键绑定。我尝试阅读有关它的Oracle教程，但这让我感到困惑。我想知道是否有人可以提供有关如何交换KeyListener以换取KeyBinding的替代教程？这也是我在这里的第一篇文章，如果格式设置已关闭，我深表歉意。

public class FightingBricks extends JPanel implements ActionListener, 
KeyListener
{
    Timer tm;

    int x1 = 0, y1 = 0, velX1 = 0, velY1 = 0;
    int x2 = 0, y2 = 0, velX2 = 0, velY2 = 0;
    int w = 1000, h = 1000;
    static int width = 1000, height = 1000;

    public  FightingBricks ()
    {
        tm = new Timer(2, this);
        tm.start(); 
        addKeyListener(this); 
        setFocusable(true); 
        setFocusTraversalKeysEnabled(false); 
    }

   public void paintComponent(Graphics g)
   {
        super.paintComponent(g);

        g.setColor(Color.red);
        g.fillRect(x1, y1, 50, 50);
        g.setColor(Color.blue);
        g.fillRect(x2, y2, 50, 50);
   }  

   public void actionPerformed(ActionEvent e)
   {
        if(x1 < 0)
        {
            x1 = 0;
            velX1 = 0;
        }
        if(x1 > w - 50)
        {
            x1 = w - 50;
            velX1 = 0;
        }
        if(y1 < 0)
        {
            y1 = 0;
            velY1 = 0;
        }
        if(y1 > h-75)
        {
            y1 = h-75;
            velY1 = 0;
        }
        x1 = x1 + velX1;
        y1 = y1 + velY1;

        if(x2<0)
        {
            velX2 = 0;
            x2 = 0;
        }

        if(x2>w-50)
        {
            velX2 = 0;
            x2 = w-50;
        }

        (y2<0)
        {
            velY2 = 0;
            y2 = 0;
        }

        if(y2>h-75)
        {
            velY2 = 0;
            y2 = h-75;
        }

        y2 = y2 + velY2;
        x2 = x2 + velX2;
        repaint();

    }

    public void keyPressed(KeyEvent e)
    {
        int c = e.getKeyCode();
        if (c == KeyEvent.VK_LEFT) // VK_Left is left arrow 
        {
            velX1 = -2;
            velY1 = 0;
        }
        if (c == KeyEvent.VK_UP) // VK_UP is up arrow 
       {
           velX1 = 0;
           velY1 = -2; // means up 
       }
        if (c == KeyEvent.VK_RIGHT)  
       {
           velX1 = 2;
           velY1 = 0; 
       }

       if (c == KeyEvent.VK_DOWN)  
       {
           velX1 = 0;
           velY1 = 2; 
       }

       if(c == KeyEvent.VK_W)
       {
          velX2 = 0;
          velY2 = -2;
       }

       if(c == KeyEvent.VK_A)
       {
           velX2 = -2;
           velY2 = 0;
       }

       if(c == KeyEvent.VK_S)
       {
           velX2 = 0;
           velY2 = 2;
       }

       if(c == KeyEvent.VK_D)
       {
           velX2 = 2;
           velY2 = 0;
       }
    }

    public void keyTyped(KeyEvent e){}

    public void keyReleased(KeyEvent e)
    {
        velX1 = 0;
        velY1 = 0;
        velX2 = 0;
        velY2 = 0;
    }

    public static void main(String[] args)
    { 
        FightingBricks fb = new  FightingBricks();
        JFrame jf = new JFrame();
        jf.setTitle("Fighting Bricks");
        jf.setSize(width, height);
        jf.setResizable(false);
        jf.setVisible(true);
        jf.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        FightingBricks fb1 = new  FightingBricks();
        jf.add(fb1);
    }
}