简单随机验证码的生成

Myth丶恋晨 2021-09-30 05:04 457阅读 0赞

**一 代码**

/**
    *
    * @ClassName: TestVerificationCode
    *
    * @Description: 随机验证码的实现
    *
    */
    import java.awt.*;
    import java.awt.event.*;
    import java.util.Random;
    import javax.swing.*;
    public class TestVerificationCode
    {
        public static void main(String[] args)
        {
            JFrame frame = new JFrame("登录测试");
            JButton b1 = new JButton("登陆");
            JButton b2 = new JButton("注册");
            JPanel center = new JPanel();
            center.setLayout(new GridLayout(0, 1, 5, 5));
            JPanel center1 = new JPanel();
            JPanel center2 = new JPanel();
            JPanel center3 = new JPanel();
            JPanel west = new JPanel();
            JTextField t1 = new JTextField(10);
            JPasswordField t2 = new JPasswordField(10);
            JTextField t3 = new JTextField(5);
            center1.setLayout(new GridLayout(1, 0));  // 仅限1行，不限列
            center2.setLayout(new GridLayout(1, 0));
            center3.setLayout(new GridLayout(1, 0, 5, 5));
            center1.add(t1);
            center2.add(t2);
            center3.add(t3);
            ValidCode valid = new ValidCode();
            center3.add(valid);
            center.add(center1);
            center.add(center2);
            center.add(center3);
            west.setLayout(new GridLayout(0, 1));
            west.add(new JLabel("账     号:"));
            west.add(new JLabel("密     码:"));
            west.add(new JLabel("验证码:"));
            JPanel south = new JPanel();
            b1.addActionListener(new ActionListener() {
                public void actionPerformed(ActionEvent e)
                {
                    if (t3.getText().equals(valid.getCode()))
                        JOptionPane.showMessageDialog(null, "验证成功");
                    else {
                        JOptionPane.showMessageDialog(null, "验证失败");
                        valid.nextCode();
                    }
                }
            });
            south.add(b1);
            south.add(b2);
            frame.setSize(275, 240);
            frame.add(west, BorderLayout.WEST);
            JLabel mes = new JLabel("   欢迎登陆邮箱");
            mes.setFont(new Font("黑体", Font.BOLD, 25));
            frame.add(mes, BorderLayout.NORTH);
            frame.add(center, BorderLayout.CENTER);
            frame.add(south, BorderLayout.SOUTH);
            frame.setVisible(true);
            frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        }
    }
    class ValidCode extends JPanel
    {
        String code;
        private Random random = new Random();
    
        public ValidCode()
        {
            setSize(100, 40);
            this.addMouseListener(new MouseAdapter() {
                public void mouseClicked(MouseEvent e)
                {
                    setSize(100, 40);
                    nextCode();
                }
            });
        }
        public String getCode()
        {
            return code;
        }
        void generateCode()
        {
            char[] codes = new char[5];
            for (int i = 0; i < 5; i++)
            {
                if (random.nextBoolean()){
                    codes[i] = (char) (random.nextInt(26) + 65);
                } else {
                    codes[i] = (char) (random.nextInt(26) + 97);
                }
            }
            this.code = new String(codes);
        }
        public void paint(Graphics g)
        {
            if (this.code == null)
            {
                generateCode();
            }
            Font myFont = new Font("Arial", Font.BOLD | Font.ITALIC, 25);
            g.setFont(myFont);
            g.setColor(Color.WHITE);
            g.fillRect(0, 0, 100, 40);
            g.setColor(Color.BLACK);
            g.drawRect(0, 0, 99, 39);
            g.setColor(Color.LIGHT_GRAY);
            for (int i = 0; i < 100; i++)
            {
                int x = random.nextInt(100 - 1);
                int y = random.nextInt(40 - 1);
                int x1 = random.nextInt(100 - 10) + 10;
                int y1 = random.nextInt(40 - 4) + 4;
                g.drawLine(x, y, x1, y1);
            }
            g.setColor(Color.RED);
            for (int i = 0; i < 5; i++)
            {
                g.drawString(code.charAt(i) + "", 16 * i + 10, 25);
            }
        }
        public void nextCode()
        {
            generateCode();
            repaint();
        }
    }

**二 运行**

![20190724214525399.png][]

[20190724214525399.png]: https://img-blog.csdnimg.cn/20190724214525399.png