12.16随笔

这里是12.16随笔
代码留档：package come;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;

@WebServlet("/DengluServlet")
public class DengluServlet extends HttpServlet {

@Override
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    String name = request.getParameter("Name");
    String role = request.getParameter("role");
    String password = request.getParameter("password");

    try {
        // 加载数据库驱动（根据你的MySQL版本可能需要调整）
        Class.forName("com.mysql.cj.jdbc.Driver");
        // 建立数据库连接
        Connection connection = DriverManager.getConnection("jdbc:mysql://localhost:3306/ygkaoqin", "root", "12345");
        String sql = "SELECT * FROM xinxi WHERE Name =? AND role =? AND password =?";
        PreparedStatement preparedStatement = connection.prepareStatement(sql);
        preparedStatement.setString(1, name);
        preparedStatement.setString(2, role);
        preparedStatement.setString(3, password);
        ResultSet resultSet = preparedStatement.executeQuery();

        if (resultSet.next()) {
            if ("员工".equals(role)) {
                response.sendRedirect("EmployeeFunction.jsp");
            } else if ("部门经理".equals(role)) {
                response.sendRedirect("ManagerFunction.jsp");
            } else if ("管理员".equals(role)) {
                response.sendRedirect("AdminFunction.jsp");
            }
        } else {
            response.sendRedirect("index.jsp?error=1");// 登录失败，返回登录页面并可以显示错误信息
        }

        resultSet.close();
        preparedStatement.close();
        connection.close();
    } catch (ClassNotFoundException | SQLException e) {
        e.printStackTrace();
    }
}

}
一个登录的逻辑