Servlet类

package Servlet;

import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

@WebServlet("/LoginServlet")
public class LoginServlet extends HttpServlet {
    private static final long serialVersionUID = 1L;

    protected void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        // Retrieve form parameters
        String username = request.getParameter("username");
        String password = request.getParameter("password");
        String role = request.getParameter("type");

        // Perform authentication logic here (e.g., check username and password against a database)

        // Redirect based on the selected role
        if ("1".equals(role)) {
            response.sendRedirect("staff.jsp"); // Redirect to employee page
        } else if ("2".equals(role)) {
            response.sendRedirect("manager.jsp"); // Redirect to manager page
        } else if ("3".equals(role)) {
            response.sendRedirect("admin.jsp"); // Redirect to CEO page
        } else if ("4".equals(role)) {
            response.sendRedirect("finance.jsp"); // Redirect to finance page
        } else {
            // Handle invalid role
            response.sendRedirect("errorPage.jsp");
        }
    }
}

package Util;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
/**
 *
 * @author llq
 *数据库连接util
 */
public class DbUtil {

    private String dbUrl = "jdbc:mysql://localhost:3306/yyy";
    //?useUnicode=true&characterEncoding=utf8";
    private String dbUser = "root";
    private String dbPassword = "ydt041113";
    private String jdbcName = "com.mysql.jdbc.Driver";
    private Connection connection = null;
    public Connection getConnection(){
        try {
            Class.forName(jdbcName);
            connection = DriverManager.getConnection(dbUrl, dbUser, dbPassword);
            System.out.println("数据库连接成功");
        } catch (Exception e) {
            // TODO Auto-generated catch block
            System.out.println("数据库连接失败");
            e.printStackTrace();
        }
        return connection;
    }

    public void closeCon(){
        if(connection != null)
            try {
                connection.close();
                System.out.println("数据库连接已关闭");
            } catch (SQLException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
    }

    public static void main(String[] args) {
        // TODO Auto-generated method stub
        //创建一个数据库对象
        DbUtil dbUtil = new DbUtil();
        //连接数据库
        dbUtil.getConnection();
    }
}