import java.awt.*;
import java.awt.event.*;
import javax.swing.*;

public class KeyGUI extends JFrame implements KeyListener{
    public KeyGUI() {
        JFrame frame = new JFrame();
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setSize(300,300);
        frame.setFocusable(true);
        frame.setVisible(true);
        frame.addKeyListener(this);
    }

    public static void main(String[] args){
        new KeyGUI();
    }

    public void keyPressed(KeyEvent e) {
        System.out.println(e.getKeyCode());
    }
    public void keyReleased(KeyEvent e) {}
    public void keyTyped(KeyEvent e) {}
}