Java：KeyListener类不检测按键，只检测密钥版本

Question

我正在构建一个非常简单的游戏来练习我的基本Java知识，而我的KeyManager课程没有响应。

package me.holdenew.game.keyinputs;

import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;

public class KeyManager implements KeyListener {

    private boolean[] keys;
    public boolean up, down, left, right;

    public KeyManager() {

        keys = new boolean[256];
    }

    public void update() {

        up = keys[KeyEvent.VK_W] || keys[KeyEvent.VK_UP];
        down = keys[KeyEvent.VK_S] || keys[KeyEvent.VK_DOWN];
        left = keys[KeyEvent.VK_A] || keys[KeyEvent.VK_LEFT];
        right = keys[KeyEvent.VK_D] || keys[KeyEvent.VK_RIGHT];
    }

    @Override
    public void keyPressed(KeyEvent e) {

        keys[e.getKeyCode()] = true;
        System.out.println(Integer.toString(e.getKeyCode()) + " pressed");
    }

    @Override
    public void keyReleased(KeyEvent e) {

        keys[e.getKeyCode()] = false;
        System.out.println(Integer.toString(e.getKeyCode()) + " released");
    }

    @Override
    public void keyTyped(KeyEvent e) {

    }
}

我添加了print语句，当我按下键时会调用它们，因此我知道该类已正确设置。但是，如果我一次按下多个键或按下一个按键并按下内容，那么所有键都没有响应，只调用keyReleased print语句，而不是{{1一个。我可以帮忙解决这个问题吗？