java 简单猜数字游戏

package p;

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

public class lc4 implements ActionListener   {
	int n=13;
	
	JFrame jf=new JFrame("Example");
		
	JTextField tf1=new JTextField(5);
	JTextField tf2=new JTextField(15);
	
	Label l=new Label("Please Input A Number:");
	
	JButton b=new JButton("Close");

	public static void main(String[] args) {
		lc4 that=new lc4();
		that.go();
	}
	
	public void go(){
		jf.getContentPane().setLayout(new FlowLayout());
		
		l.setBackground(Color.yellow);
		tf1.setBackground(Color.green);
		tf2.setBackground(Color.red);
		b.setBackground(Color.gray);
		
		jf.getContentPane().add(l);
		jf.getContentPane().add(tf1);
		jf.getContentPane().add(tf2);
		jf.getContentPane().add(b);
		
		tf1.addActionListener(this);
		tf2.addActionListener(this);
		b.addActionListener(this);
		
		jf.pack();
		jf.setVisible(true);
	}
	public void actionPerformed(ActionEvent e) {
		
		if(n==Integer.valueOf(tf1.getText())){
			tf2.setText("U R Right!");
		}
		else if(n<Integer.valueOf(tf1.getText())){
			tf2.setText("Bigger!");
		}
		else{
			tf2.setText("Smaller!");
		}
		
		if((JButton)e.getSource()==b){
			System.exit(0);
		}
	}

}