用户名和密码正确不跳转

# 具体遇到的问题

# 报错信息的截图

# 相关课程内容截图

# 尝试过的解决思路和结果

# 粘贴全部相关代码，切记添加代码注释（请勿截图）

在这里输入代码，可通过选择【代码语言】突出显示

<?xml version="1.0" encoding="UTF-8"?>

<c3p0-config>

  <default-config>

    <property name="driverClass">com.mysql.cj.jdbc.Driver</property>

    <property name="jdbcUrl">jdbc:mysql:///shop</property>

    <property name="user">root</property>

    <property name="password">lyt147369258</property>

  </default-config>

</c3p0-config>

package com.imooc.dao.impl;

import java.sql.Connection;

import java.sql.PreparedStatement;

import java.sql.ResultSet;

import com.imooc.dao.UserDao;

import com.imooc.domain.User;

import com.imooc.utils.JDBCUtils;

public class UserDaoImpl implements UserDao {

@Override

public User login(User user) {

Connection conn=null;

PreparedStatement pstmt=null;

ResultSet res=null;

try {

//连接数据

conn=JDBCUtils.getConnection();

//编写sql

String sql="slect * from user where username=? and password=?";

//预编译sql

pstmt=conn.prepareStatement(sql);

//设置值

pstmt.setString(1, user.getUsername());

pstmt.setString(2, user.getPassword());

res=pstmt.executeQuery();

//取得结果集

if(res.next()) {

//将结果集放入User数据中

User users=new User();

users.setUsername(res.getString("username"));

users.setUid(res.getInt("uid"));

users.setPassword(res.getString("password"));

return users;

}

}catch(Exception e) {

e.printStackTrace();

}finally {

//释放资源

JDBCUtils.release(res, pstmt, conn);

}

return null;

}

}

package com.imooc.web.action;

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;

import com.imooc.domain.User;

import com.imooc.service.UserService;

import com.imooc.service.impl.UserServiceImpl;

@WebServlet("/UserServlet")

public class UserServlet extends HttpServlet {

private static final long serialVersionUID = 1L;

protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {

//接受前台传入的数据

String s=request.getParameter("method");

if("login".equals(s)) {

login(request,response);

}else if("logout".equals(s)) {

logout(request,response);

}

}

private void logout(HttpServletRequest request, HttpServletResponse response) throws IOException {

//1、销毁session

request.getSession().invalidate();

//2、进行重定向

response.sendRedirect(request.getContextPath()+"/admin/login.jsp");

}

/**

 * 实现登录操作

 * @param request

 * @param response

 * @throws IOException 

 * @throws ServletException 

 */

private void login(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {

String username=request.getParameter("username");

String password=request.getParameter("password");

System.out.println(username+password);

//封装数据

User user=new User();

user.setUsername(username);

user.setPassword(password);

//处理数据

   UserService userservice=new UserServiceImpl();

   //返回值是User，参数为user

  User users=userservice.login(user);

//处理完数据后，完成页面跳转

  if(users==null) {

  //登录失败

  //返回登录页面

  request.setAttribute("msg", "用户名或者密码错误");

  //请求的转发

  request.getRequestDispatcher("/admin/login.jsp").forward(request, response);

  //登录成功

  //将用户信息进行保存，进行页面的跳转

  request.getSession().setAttribute("users", users);

  //进行重定向

response.sendRedirect(request.getContextPath()+"/admin/category_list.jsp");

  }

}

 

protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {

doGet(request, response);

}

}

错误提示：

java.sql.SQLException: The server time zone value '?й???????' is unrecognized or represents more than one time zone. You must configure either the server or JDBC driver (via the serverTimezone configuration property) to use a more specifc time zone value if you want to utilize time zone support.

Caused by: com.mysql.cj.exceptions.InvalidConnectionAttributeException: The server time zone value '?й???????' is unrecognized or represents more than one time zone. You must configure either the server or JDBC driver (via the serverTimezone configuration property) to use a more specifc time zone value if you want to utilize time zone support.

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