compiler-errors - KeyListener 错误

Question

我在将 keyListener 添加到我的应用程序时遇到问题：

App.Game不是抽象的，并且不会覆盖keyRelased(java.awt.event.KeyEvent)java.awt.event.KeyListener 中的抽象方法

我尝试创建新的公共课程KeyAdapt。它给出了同样的错误。
我的应用程序代码是：

public int x = 100, y = 100;
public class Game extends JFrame implements KeyListener {
    public Game() {
        super();
        setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
        setLocationRelativeTo(null);
        setUndecorated(true);
        setLayout(null);
        setVisible(true);
    }
    public void paint (Graphics gDC) {
        gDC.clearRect(0, 0, getSize().width, getSize().height);
        getGraphics().drawOval(x, y, 20, 20);
    }
    public void keyPressed(KeyEvent e) {
        if (e.getKeyCode() == KeyEvent.VK_UP ) {
            y++;
        }
        if (e.getKeyCode() == KeyEvent.VK_DOWN ) {
            y--;
        }
        if (e.getKeyCode() == KeyEvent.VK_RIGHT ) {
            x++;
        }
        if (e.getKeyCode() == KeyEvent.VK_LEFT ) {
            x--;
        }
    }
    public void keyRelased(KeyEvent e) {
        if (e.getKeyCode() == KeyEvent.VK_UP ) {
            y+=0;
        }
        if (e.getKeyCode() == KeyEvent.VK_DOWN ) {
            y-=0;
        }
        if (e.getKeyCode() == KeyEvent.VK_RIGHT ) {
            x+=0;
        }
        if (e.getKeyCode() == KeyEvent.VK_LEFT ) {
            x-=0;
        }
    }
    public void keyTyped(KeyEvent e) {}
}