KeyListener键盘监听器

import javax.swing.*;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;
//KeyListener:键盘监听
public class KeyListenerTest1 {
    public static void main(String[] args) {
        JFrame f=new JFrame();
        f.setSize(500,500);
        f.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
        f.addKeyListener(new KeyListener() {
            @Override
            public void keyTyped(KeyEvent e) {

            }

            @Override
            public void keyPressed(KeyEvent e) {
                int keyCode=e.getKeyCode();
                if (keyCode==37){
                    System.out.println("向左执行");
                }else if (keyCode==38){
                    System.out.println("向上执行");
                }else if (keyCode==39){
                    System.out.println("向右执行");
                }else if (keyCode==40){
                    System.out.println("向下执行");
                }
            }

            @Override
            public void keyReleased(KeyEvent e) {

            }
        });
        f.setVisible(true);
    }
}