java 谁帮我运行下错在哪?

//楼主注意下接口函数名字由其是大小写，java是区分大小写的。下边就OK了.

import java.awt.*;
import java.awt.event.*;

import javax.swing.*;

public class Key_press extends JFrame implements KeyListener {
private String line1 = "", line2 = "";
private JTextArea text;

public Key_press() {
super("显示键盘事件演示程序");
text = new JTextArea(10, 15);
text.setText("按任意键继续...");
text.setEnabled(false);
text.setFont(new Font("TimesRoman", Font.BOLD + Font.ITALIC, 14));
getContentPane().add(text);
addKeyListener(this);
setSize(500, 400);
show();
}

public void keyPressed(KeyEvent e){
line1 = "键盘按下:" + e.getKeyText(e.getKeyCode());
setString(e);
}

public void keyReleased(KeyEvent e){
line1 = "键盘释放:" + e.getKeyText(e.getKeyCode());
setString(e);
}

public