package com.bipt.service;


import com.bipt.pojo.User;

/**
 * @author 不止于夢想
 * @date 2022/10/3 20:04
 */
public interface UserService {
    /**
     * 登錄方法
     */
      User login(String username,String password);
    /**
     * 注冊方法
     */
    int register(String username,String password);
}

package com.bipt.service.implService;

import com.bipt.mapper.UserMapper;
import com.bipt.pojo.User;
import com.bipt.service.UserService;
import com.bipt.utils.SqlSessionFactoryUtils;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;

/**
 * @author 不止于夢想
 * @date 2022/10/3 20:16
 */
public class ImplUserService implements UserService {
    SqlSessionFactory sessionFactory = SqlSessionFactoryUtils.getSqlSessionFactory();
    @Override
    public  User login(String username,String password) {
        SqlSession session =sessionFactory .openSession();
        UserMapper mapper = session.getMapper(UserMapper.class);
        User user = mapper.select(username, password);
        return user;
    }

    @Override
    public int register(String username,String password) {
        SqlSession session =sessionFactory .openSession();
        UserMapper mapper = session.getMapper(UserMapper.class);
        int flag = mapper.addUser(username,password);
        return flag;
    }
}

```package com.bipt.controller;

import com.bipt.pojo.User;
import com.bipt.service.implService.ImplUserService;

import javax.servlet.ServletException;
import javax.servlet.http.*;
import java.io.IOException;

/**
 * 用戶登錄的servlet
 * @author 不止于夢想
 * @date 2022/10/3 18:26
 */
//@WebServlet("/loginServlet")
public class LoginServlet extends HttpServlet {
    private ImplUserService implUserService = new ImplUserService();
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        //獲取用戶名信息
        String username = req.getParameter("username");
        //獲取密碼
        String password = req.getParameter("password");
        //獲取記住狀態(tài)
        String remember = req.getParameter("remember");
        //獲取訪問的項目路徑
        String contextPath = req.getContextPath();
        //查詢客戶是否存在
        User user = implUserService.login(username,password);
        System.out.println(user.getName());
        System.out.println(user.getPassword());
        //判斷用戶是否為真
        if(user != null){
            //判斷用戶是否勾選了記住我選項
            if("1".equals(remember)){
                //為真，則創(chuàng)建cookie
               Cookie cookie1 = new Cookie("username",username);
                Cookie cookie2 = new Cookie("password",password);
                //設(shè)置cookie的存活時長,設(shè)置為兩天半
                //cookie中無法設(shè)置double數(shù)據(jù)，那么兩天半等于多少秒呢--21600秒，我們直接設(shè)置秒數(shù)
//                cookie1.setMaxAge(60*60*24*2.5);這樣是不行的
                cookie1.setMaxAge(21600);
                cookie2.setMaxAge(21600);
                //綁定路徑--任意路徑訪問均可
                cookie1.setPath("/");
                cookie2.setPath("/");
                //發(fā)送cookie到客戶端
                resp.addCookie(cookie1);
                resp.addCookie(cookie2);
            }
            //把對象存儲到session域中，便于過濾器使用
            HttpSession session = req.getSession();
            session.setAttribute("user",user);
            //表示成功,跳轉(zhuǎn)到歡迎頁面
            resp.sendRedirect(""+contextPath+"/index.html");
        }else{
            req.getRequestDispatcher(""+contextPath+"/login.jsp").forward(req,resp);

        }


}

    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        this.doGet(req,resp);
    }
}

***執(zhí)行注冊控制的loginServlet：***
```java
package com.bipt.controller;
import com.bipt.service.implService.ImplUserService;
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.io.Writer;

/**
 * @author 不止于夢想
 * @date 2022/10/5 13:42
 */
@WebServlet("/registerServlet")
public class RegisterServlet extends HttpServlet {
    private ImplUserService implUserService = new ImplUserService();
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        //獲取數(shù)據(jù)
        String username = req.getParameter("username");
        String password = req.getParameter("password");
        //獲取訪問的項目路徑
        String contextPath = req.getContextPath();
        //添加用戶，返回1表示添加成功，返回登錄界面，返回0表示失敗，返回注冊界面
        int flag = implUserService.register(username,password);
        if("1".equals(flag)){
            resp.sendRedirect(contextPath+"/login.jsp");
        }else{
            resp.sendRedirect(contextPath+"/register.jsp");
        }

    }

    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        this.doGet(req, resp);
    }
}

package com.bipt.utils;

import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.Cookie;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpSession;
import java.io.IOException;

/**
 * @author 不止于夢想
 * @date 2022/10/5 22:03
 */
@WebFilter(filterName = "loginFilter",urlPatterns = "*.html")
public class LoginFilter implements Filter {
    @Override
    public void doFilter(ServletRequest req, ServletResponse resp, FilterChain filterChain) throws IOException, ServletException {
       HttpServletRequest httpServletRequest = (HttpServletRequest) req;
      HttpSession session = httpServletRequest.getSession();
//      String uri = ((HttpServletRequest) req).getRequestURI();
//        int startPos = uri.lastIndexOf(".");
//        String result = uri.substring(startPos);
        Object user = session.getAttribute("user");
        if(user==null){
        httpServletRequest.getRequestDispatcher(
                httpServletRequest.getContextPath()+"/login.jsp").forward(req,resp);
        return;
        } else filterChain.doFilter(req,resp);//否則則繼續(xù)執(zhí)行
    }
}

package com.bipt.controller;

import com.bipt.pojo.User;
import com.bipt.service.implService.ImplUserService;

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

/**
 *
 * 實現(xiàn)登錄檢查
 * @author 不止于夢想
 * @date 2022/10/5 19:37
 */
@WebServlet("/logCheckServlet")
public class LogCheckServlet extends HttpServlet {
    private ImplUserService implUserService = new ImplUserService();
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {

        String username=null;
        String password=null;
        Cookie[] cookies = req.getCookies();
        for (Cookie cookie:cookies) {
            if("username".equals(cookie.getName())){
                username = cookie.getValue();
            }else if("password".equals(cookie.getName())){
                password = cookie.getValue();
            }
        }
        /**
         * 判斷username和password的值是否為空，如果不為空，則查詢數(shù)據(jù)庫，查到則轉(zhuǎn)發(fā)到歡迎界面
         */
        if(username != null &&password != null){
            //調(diào)用查詢語句
            User user = implUserService.login(username,password);
            if(user!=null){
                resp.sendRedirect(req.getContextPath()+"index.html");
            }
            else {
                resp.sendRedirect(req.getContextPath()+"/login.jsp");
            }
        }
    }

    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        this.doGet(req,resp);
    }
}