jsp更新mysql数据库数据

<%@ page import="java.sql.*" %>
<%
    String url = "jdbc:mysql://localhost:3306/mydatabase";
    String username = "user";
    String password = "password";

    Connection conn = null;
    PreparedStatement pstmt = null;

    try {
        // 加载JDBC驱动
        Class.forName("com.mysql.jdbc.Driver");

        // 建立连接
        conn = DriverManager.getConnection(url, username, password);

        // 准备SQL语句
        String sql = "UPDATE users SET email = ? WHERE id = ?";
        pstmt = conn.prepareStatement(sql);

        // 设置参数
        pstmt.setString(1, "newemail@example.com");
        pstmt.setInt(2, 1);

        // 执行更新
        int rowsUpdated = pstmt.executeUpdate();

        if (rowsUpdated > 0) {
            out.println("数据更新成功！");
        } else {
            out.println("没有找到匹配的数据进行更新。");
        }
    } catch (ClassNotFoundException | SQLException e) {
        out.println("数据库操作失败: " + e.getMessage());
    } finally {
        // 关闭资源
        try {
            if (pstmt != null) pstmt.close();
            if (conn != null) conn.close();
        } catch (SQLException e) {
            out.println("关闭数据库连接失败: " + e.getMessage());
        }
    }
%>