java mysql swing 登录注册页面带有验证码 代码实现

好的，以下是一个简单的 Java Swing 登录页面，其中包含验证码的实现。假设您已经有了生成验证码图片的方法，我将在代码中使用一个名为 `generateCaptcha()` 的方法来代表该方法。此外，我们还将使用 MySQL 数据库来存储用户信息。

import java.awt.*;
import java.awt.event.*;
import java.awt.image.BufferedImage;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import javax.imageio.ImageIO;
import javax.swing.*;
import java.sql.*;

public class LoginFrame extends JFrame implements ActionListener {
    private JLabel usernameLabel, passwordLabel, captchaLabel;
    private JTextField usernameField;
    private JPasswordField passwordField;
    private JButton loginButton, registerButton, refreshButton;
    private JPanel mainPanel, inputPanel, buttonPanel, captchaPanel;
    private BufferedImage captchaImage;
    private String captchaText;
    private Connection conn;

    public LoginFrame() {
        initGUI();
        initDB();
        generateCaptcha();
    }

    private void initGUI() {
        // 设置窗口标题和大小
        setTitle("Login");
        setSize(400, 300);
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        setLocationRelativeTo(null);

        // 创建输入框和标签
        usernameLabel = new JLabel("Username:");
        passwordLabel = new JLabel("Password:");
        captchaLabel = new JLabel("Captcha:");
        usernameField = new JTextField(20);
        passwordField = new JPasswordField(20);

        // 创建验证码相关组件
        captchaPanel = new JPanel();
        refreshButton = new JButton("Refresh");
        refreshButton.addActionListener(this);
        captchaPanel.add(refreshButton);

        // 创建登录和注册按钮
        loginButton = new JButton("Login");
        loginButton.addActionListener(this);
        registerButton = new JButton("Register");
        registerButton.addActionListener(this);

        // 将组件添加到输入面板和按钮面板
        inputPanel = new JPanel(new GridLayout(3, 2));
        inputPanel.add(usernameLabel);
        inputPanel.add(usernameField);
        inputPanel.add(passwordLabel);
        inputPanel.add(passwordField);
        inputPanel.add(captchaLabel);
        inputPanel.add(captchaPanel);

        buttonPanel = new JPanel(new FlowLayout(FlowLayout.CENTER));
        buttonPanel.add(loginButton);
        buttonPanel.add(registerButton);

        // 将输入面板和按钮面板添加到主面板
        mainPanel = new JPanel(new BorderLayout());
        mainPanel.add(inputPanel, BorderLayout.CENTER);
        mainPanel.add(buttonPanel, BorderLayout.SOUTH);

        // 将主面板添加到窗口
        add(mainPanel);
    }

    private void initDB() {
        try {
            // 加载 MySQL 驱动
            Class.forName("com.mysql.cj.jdbc.Driver");

            // 连接到数据库
            String url = "jdbc:mysql://localhost:3306/mydb";
            String user = "root";
            String password = "password";
            conn = DriverManager.getConnection(url, user, password);
        } catch (ClassNotFoundException ex) {
            ex.printStackTrace();
        } catch (SQLException ex) {
            ex.printStackTrace();
        }
    }

    private void generateCaptcha() {
        // 生成验证码图片和文本
        captchaText = generateRandomString(6);
        captchaImage = new BufferedImage(120, 30, BufferedImage.TYPE_INT_RGB);
        Graphics2D g2d = captchaImage.createGraphics();
        g2d.setColor(Color.WHITE);
        g2d.fillRect(0, 0, 120, 30);
        g2d.setColor(Color.BLACK);
        g2d.setFont(new Font("Arial", Font.BOLD, 20));
        g2d.drawString(captchaText, 10, 20);
        g2d.dispose();

        // 将验证码图片添加到面板
        JLabel captchaImageLabel = new JLabel(new ImageIcon(captchaImage));
        captchaPanel.removeAll();
        captchaPanel.add(captchaImageLabel);
        captchaPanel.add(refreshButton);
        captchaPanel.revalidate();
    }

    private String generateRandomString(int length) {
        String chars = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789";
        StringBuilder sb = new StringBuilder(length);
        for (int i = 0; i < length; i++) {
            sb.append(chars.charAt((int) (Math.random() * chars.length())));
        }
        return sb.toString();
    }

    private boolean validateCaptcha(String input) {
        return input.equalsIgnoreCase(captchaText);
    }

    private boolean validateLogin(String username, String password) {
        try {
            String sql = "SELECT * FROM users WHERE username = ? AND password = ?";
            PreparedStatement stmt = conn.prepareStatement(sql);
            stmt.setString(1, username);
            stmt.setString(2, password);
            ResultSet rs = stmt.executeQuery();
            return rs.next();
        } catch (SQLException ex) {
            ex.printStackTrace();
            return false;
        }
    }

    private boolean insertUser(String username, String password) {
        try {
            String sql = "INSERT INTO users (username, password) VALUES (?, ?)";
            PreparedStatement stmt = conn.prepareStatement(sql);
            stmt.setString(1, username);
            stmt.setString(2, password);
            int result = stmt.executeUpdate();
            return result > 0;
        } catch (SQLException ex) {
            ex.printStackTrace();
            return false;
        }
    }

    @Override
    public void actionPerformed(ActionEvent e) {
        if (e.getSource() == loginButton) {
            String username = usernameField.getText();
            String password = new String(passwordField.getPassword());
            String captcha = JOptionPane.showInputDialog(this, "Please enter the captcha:");
            if (validateCaptcha(captcha)) {
                if (validateLogin(username, password)) {
                    JOptionPane.showMessageDialog(this, "Login successful!");
                } else {
                    JOptionPane.showMessageDialog(this, "Invalid username or password.");
                }
            } else {
                JOptionPane.showMessageDialog(this, "Invalid captcha.");
                generateCaptcha();
            }
        } else if (e.getSource() == registerButton) {
            String username = usernameField.getText();
            String password = new String(passwordField.getPassword());
            if (insertUser(username, password)) {
                JOptionPane.showMessageDialog(this, "User registered successfully!");
            } else {
                JOptionPane.showMessageDialog(this, "Failed to register user.");
            }
        } else if (e.getSource() == refreshButton) {
            generateCaptcha();
        }
    }

    public static void main(String[] args) {
        LoginFrame frame = new LoginFrame();
        frame.setVisible(true);
    }
}

这个示例代码中，我们使用了三个方法来验证用户输入的验证码、验证用户登录信息和向数据库中插入新用户。当用户点击登录按钮时，我们会弹出一个对话框来让用户输入验证码。如果验证码正确，我们将验证用户输入的用户名和密码是否正确，并给出相应的提示。当用户点击注册按钮时，我们将向数据库中插入新用户的信息。当用户点击刷新验证码按钮时，我们将生成新的验证码图片并更新面板。

上述代码仅供参考，您可以根据您的需求进行修改和扩展。