猜数字游戏

功能：产生一个随机数，猜随机数的大小，机会只有3次，并且如果猜错了，焦点自动返回。
使用到的接口：ActionListener FocusListener;

代码：

package com.niit.guessgame;

import java.awt.Color;
import java.awt.FlowLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.FocusEvent;
import java.awt.event.FocusListener;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import java.util.Random;

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JOptionPane;
import javax.swing.JTextField;

/**
 * 
 */

/**
 * @author Annie
 * @date 2016年6月6日
 * @description:猜数字游戏(用到了焦点事件，活动事件)
 */
public class GuessGame extends JFrame implements ActionListener,FocusListener{
    public static void main(String[] args) {
        new GuessGame();
    }

    JLabel hintLabel;
    JButton buttonGetNumber,buttonEnter;
    JTextField inputText;
    Random random;
    int number ;
    int count =1;
    int i =3;
    public GuessGame() {
        super("猜数字");
        setLayout(new FlowLayout());
        setSize(300, 300);
        buttonGetNumber = new JButton("得到一个随机数：");
        hintLabel = new JLabel("输入你猜的数字",JLabel.CENTER);
        hintLabel.setBackground(Color.cyan);
        inputText = new JTextField(10);
        buttonEnter = new JButton("确定");
        add(buttonGetNumber);
        add(hintLabel);
        add(inputText);
        add(buttonEnter);
        setVisible(true);
        buttonGetNumber.addActionListener(this);
        buttonEnter.addActionListener(this);
        inputText.addFocusListener(this);
        inputText.requestFocusInWindow();
        addWindowListener(new WindowAdapter() {

            @Override
            public void windowClosing(WindowEvent e) {
                super.windowClosing(e);
                dispose();
            }
        });
    }

    @Override
    public void actionPerformed(ActionEvent e) {
        if(e.getSource() == buttonGetNumber){
            random = new Random();
            number    = random.nextInt(1000);
            hintLabel.setText("请输入你要猜的数字：");
        }else if(e.getSource() == buttonEnter){
            int guess = Integer.valueOf(inputText.getText());
            if(number ==  guess){
                hintLabel.setText("猜对了！");
            }else if(number >guess){
                count++;
                i--;
                hintLabel.setText("猜小了,你还有:"+i+"次机会,请继续输入");
                inputText.requestFocusInWindow();

            }else if (number < guess){
                count++;
                i--;
                hintLabel.setText("猜大了,你还有:"+i+"次机会,请继续输入");
                inputText.requestFocusInWindow();//获取焦点

            }
        }
        if(count > 3){
            JOptionPane.showConfirmDialog(getParent(), "game over");
            
        }
    }


    @Override
    public void focusGained(FocusEvent e) {
        inputText = (JTextField) e.getSource();
        inputText.setText(null);

    }

    @Override
    public void focusLost(FocusEvent e) {
        // TODO Auto-generated method stub

    }
}

效果图：