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基于Tomcat实现登录过滤、分页、以及servlet增删改查 ——一套完整流程

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基于Tomcat实现登录过滤、分页、以及servlet增删改查 ——一套完整流程

文章目录
  • 前言
  • 一、实现效果图展示
  • 二、代码
    • 1.项目结构
    • 2.具体代码
  • 总结

前言

本内容主要运用了servlet,ajax 来实现前端对后台数据的传输，以及过滤 filter来实现没有登录成功之前，不能访问我们要增删改查的信息。必须注册用户登录成功之后，才能正常访问我们的数据页面。适合刚学习servlet的小伙伴。

一、效果图展示

 

 

 

 

二、代码 1.项目结构

 

2.代码

代码如下（示例）：

login.jsp中

<%--
  Created by IntelliJ IDEA.
  User: 22743
  Date: 2022/7/26
  Time: 0:16
  To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>


    登录
    
    
    
    

    

    
        <%--登录界面--%>
        
    
        

            
                
                    
                        
                            
                            
登陆界面
                        
                        
                            
                                
                                    
                                    
                                
                                
                                    
                                    
                                
                            
                        
                        
                            
                            
<%--                            --%>
                            
                        
                    
                
            
        

    <%--注册界面--%>
    

        
            
                
                    
                        
                        
注册界面
                    
                    
                        
                            
                                
                                
                            
                            
                                
                                
                            
                            
                                
                                
                            
                        
                    
                    
                        
                        
<%--                    --%>
                        <%--                        --%>

user_self.jsp代码块

<%--
  Created by IntelliJ IDEA.
  User: 22743
  Date: 2022/7/25
  Time: 11:24
  To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>


    用户列表
    
    
    
    



    

        
            
        
        
            

                
                    
                    
                
                
                    
                    
                
                
            

        
    
<%--    --%>
    
                <%-- --%>
                

        
            
序号用户名
                年龄
                性别
                电话
                操作
            

        
        
        
        

            
                
    
                		
        
    
            
    
    


<%--     查询--%>
<%--    --%>
<%--        --%>
<%--            --%>
<%--                --%>
<%--                    --%>
<%--                    
    查询用户--%>
<%--                --%>
<%--                --%>
<%--                    
    --%>
<%--                        --%>
<%--                            --%>
<%--                            --%>
<%--                        --%>
<%--                    
    --%>
<%--                --%>
<%--                --%>
<%--                    --%>
<%--                    --%>
<%--                --%>
<%--            --%>
<%--        --%>
<%--    --%>



    
    
        
            
                
                    
                    
    用户修改
                
                
                    
    
                        
                        
                            
                            
                                
                            
                        
                        
                            
                            
                                
                            
                        
                        
                            
                            
                                
                                
                            
                        
                        
                            
                            
                                
                            
                        
                    
    
                
                
                    
                    
                
            
        
    


    
    
        
            
                
                    
                    
    添加用户

    controller 层代码块

    package com.hqyj.psl.controller;

import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.hqyj.psl.entity.Administrator;
import com.hqyj.psl.entity.User;
import com.hqyj.psl.service.UserService;
import com.hqyj.psl.service.impl.UserServiceImpl;
import com.hqyj.psl.utils.PageUtil;

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.UnsupportedEncodingException;
import java.sql.SQLException;
import java.util.List;

@WebServlet("/user")
public class UserController extends HttpServlet {
    private UserService  us = new UserServiceImpl();
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) {
        String method = req.getParameter("method");
        try {
            if (method.equals("queryUserAll")){
               queryUserAll(req,resp);
            }else if (method.equals("deleteUser")){
                deleteUser(req,resp);
            }else if (method.equals("findUserById")){
                findUserById(req,resp);
            }else if (method.equals("updateUserById")){
                updateUser(req,resp);
            }else if (method.equals("insertUser")){
                insertUser(req,resp);
            }else if (method.equals("selectUserByName")){
                selectUserByName(req,resp);
            }else if (method.equals("queryUser")){
                queryUserPage(req,resp);
            }else if (method.equals("searchUser")){
                    searchUser(req,resp);
            }
        } catch (SQLException | IOException e) {
            e.printStackTrace();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        doGet(req, resp);
    }
    public void  searchUser(HttpServletRequest req, HttpServletResponse resp) throws IOException {
        String userName = req.getParameter("userName");
        String userTel = req.getParameter("userTel");
        User user = new User();
        user.setUserName(userName);
        user.setUserTel(userTel);
        System.out.println(user);
        List users = us.searchUser(user);
        ObjectMapper mapper = new ObjectMapper();
        String s = mapper.writeValueAsString(users);
        resp.getWriter().write(s);
    }

    public void queryUserPage(HttpServletRequest req, HttpServletResponse resp) throws IOException {
        String pageNum = req.getParameter("pageNum");
        int i = Integer.parseInt(pageNum);
        if (i==-1){
            i=1;
        }
        String pageSize = req.getParameter("pageSize");
        int i1 = Integer.parseInt(pageSize);
        PageUtil userPageUtil = us.queryUserPage(i, i1);
        ObjectMapper mapper = new ObjectMapper();
        String json = mapper.writeValueAsString(userPageUtil);
        resp.getWriter().write(json);
    }


    public void selectUserByName(HttpServletRequest req, HttpServletResponse resp) throws IOException {
        req.setCharacterEncoding("UTF-8");
        String userName = req.getParameter("userName");
        List users = us.selectUserById(userName);
//        System.out.println(users);
        resp.setContentType("text/html;charset=UTF-8");
        ObjectMapper mapper = new ObjectMapper();
        String s = mapper.writeValueAsString(users);
        resp.getWriter().write(s);

    }


    public void findUserById(HttpServletRequest req, HttpServletResponse resp) throws Exception{
        String id = req.getParameter("id");
        resp.setContentType("text/html;charset=UTF-8");
        int i = Integer.parseInt(id);
        User userById = us.findUserById(i);
        ObjectMapper mapper = new ObjectMapper();
        String json = mapper.writeValueAsString(userById);
        resp.getWriter().write(json);
    }


    public void deleteUser(HttpServletRequest req, HttpServletResponse resp) throws Exception {
        String id = req.getParameter("id");
        int num = Integer.parseInt(id);
        String s = us.removeUserById(num);
//        System.out.println(s);
        resp.setContentType("text/html;charset=UTF-8");
        resp.getWriter().write(s);
    }

    public void updateUser(HttpServletRequest req, HttpServletResponse resp) throws Exception{
        resp.setContentType("text/html;charset=UTF-8");
        User user = new User();
        String id = req.getParameter("id");
        int i = Integer.parseInt(id);
        user.setId(i);
        user.setUserName(req.getParameter("userName"));
        user.setUserAge(req.getParameter("userAge"));
        user.setUserSex(req.getParameter("userSex"));
        user.setUserTel(req.getParameter("userTel"));
//        System.out.println(user);
        String s = us.updateUserById(user);
        resp.getWriter().write(s);
    }

    public void queryUserAll(HttpServletRequest req, HttpServletResponse resp) throws IOException, SQLException {
        List users = us.findUserAll();
        resp.setContentType("text/html;charset=UTF-8");
        ObjectMapper mapper = new ObjectMapper();
        String json = mapper.writeValueAsString(users);
        resp.getWriter().write(json);
    }

    public void insertUser(HttpServletRequest req, HttpServletResponse resp) throws Exception{
//        req.setCharacterEncoding("UTF-8");

        User user = new User();
        user.setUserName(req.getParameter("userName"));
        user.setUserAge(req.getParameter("userAge"));
        user.setUserSex(req.getParameter("userSex"));
        user.setUserTel(req.getParameter("userTel"));
//        System.out.println(user);
        String s = us.insertUser(user);
        resp.setContentType("text/html;charset=UTF-8");
        resp.getWriter().write(s);
    }


}

    service层代码块

    package com.hqyj.psl.service.impl;

import com.hqyj.psl.dao.UserDao;
import com.hqyj.psl.dao.impl.UserDaoImpl;
import com.hqyj.psl.entity.Administrator;
import com.hqyj.psl.entity.User;
import com.hqyj.psl.service.UserService;
import com.hqyj.psl.utils.PageUtil;

import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;

public class UserServiceImpl implements UserService {
    private UserDao userDao = new UserDaoImpl();
    @Override
    public List findUserAll() throws SQLException {
        return userDao.queryUserAll();
    }

    @Override
    public String removeUserById( int id) throws Exception {
        int i = userDao.deleteUserById(id);
        if (i>0){
            return "success";
        }else
        return "fail";
    }

    @Override
    public User findUserById(int id) {
        return userDao.findUserById(id);
    }

    @Override
    public String updateUserById(User user) {
        int i = userDao.updateUserById(user);
        if (i>0){
            return "success";
        }else {
            return "fail";
        }
    }

    @Override
    public String insertUser(User user) {
        int i = userDao.insertUser(user);
        if (i>0){
            return "success";
        }else {
            return "fail";
        }
    }

    @Override
    public List selectUserById(String userName) {
        return userDao.selectUserById(userName);
    }

    @Override
    public String enrollUser(Administrator administrator) {
        int i = userDao.enrollUser(administrator);
        if (i>0){
            return "success";
        }else {
            return "fail";
        }
    }

    @Override
    public String selectEnrollUser(Administrator administrator) {
        if (userDao.selectEnrollUser(administrator)!=null){
            return "success";
        }else {
            return "fail";
        }

    }

    @Override
    public PageUtil queryUserPage(int pageNum, int pageSize) {
        PageUtil pageUtil = new PageUtil<>();
        pageUtil.setPageNum(pageNum);
        pageUtil.setPassSize(pageSize);
        pageUtil.setTotalCount(userDao.countUserAll());
        pageUtil.setPageInfo(userDao.queryUserPage(pageNum,pageSize));
        return pageUtil;
    }

    @Override
    public List searchUser(User user) {
        List users = userDao.searchUser(user);
        if (users==null){
            List objects = new ArrayList<>();
            return objects;
        }
        return users;
    }
}

    dao 层代码块

    package com.hqyj.psl.dao.impl;

import com.hqyj.psl.dao.UserDao;
import com.hqyj.psl.entity.Administrator;
import com.hqyj.psl.entity.User;
import com.hqyj.psl.utils.DBUtils;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;

public class UserDaoImpl implements UserDao {
    private Connection conn=null;
    private PreparedStatement ps = null;
    private ResultSet rs = null;

    @Override
    public List queryUserAll() throws SQLException {
        try {
            conn = DBUtils.getConn();
            String sql="select * from user";
            ps = conn.prepareStatement(sql);
            rs = ps.executeQuery();
            ArrayList users = new ArrayList<>();
            while (rs.next()){
                User user = new User();
                user.setId(rs.getInt("id"));
                user.setUserName(rs.getString("user_Name"));
                user.setUserSex(rs.getString("user_sex"));
                user.setUserAge(rs.getString("user_age"));
                user.setUserTel(rs.getString("user_tel"));
                users.add(user);
            }
            return users;
        } catch (SQLException e) {
            e.printStackTrace();
            return null;
        } finally {
            DBUtils.close(rs,ps,conn);
        }
    }

    @Override
    public int deleteUserById(int id) {
        try {
            conn = DBUtils.getConn();
            String sql="delete  from user where id = ?";
            ps = conn.prepareStatement(sql);
            ps.setInt(1,id);
            int i = ps.executeUpdate();
            return i;
        } catch (Exception e) {
            return 0;
        } finally {
            DBUtils.close(rs,ps,conn);
        }
    }

    @Override
    public User findUserById(int id) {
        try {
            conn = DBUtils.getConn();
            String sql = "select * from user where id = ?";
            ps = conn.prepareStatement(sql);
            ps.setInt(1, id);
            rs = ps.executeQuery();
            if (rs.next()) {
                User user = new User();
                user.setId(rs.getInt("id"));
                user.setUserName(rs.getString("user_Name"));
                user.setUserSex(rs.getString("user_sex"));
                user.setUserAge(rs.getString("user_age"));
                user.setUserTel(rs.getString("user_tel"));
                return user;
            }
            return null;
        } catch (SQLException e) {
            e.printStackTrace();
            return null;
        } finally {
            DBUtils.close(rs, ps, conn);
        }
    }

    @Override
    public int updateUserById(User user) {
        try {
            conn = DBUtils.getConn();
            String sql = "update user set user_name=?,user_age=?,user_sex=?,user_tel=? where id=?";
            ps = conn.prepareStatement(sql);
            ps.setString(1, user.getUserName());
            ps.setString(2,user.getUserAge());
            ps.setString(3,user.getUserSex());
            ps.setString(4,user.getUserTel());
            ps.setInt(5,user.getId());
            int i = ps.executeUpdate();
            return i;
        } catch (SQLException e) {
            e.printStackTrace();
            return 0;
        } finally {
            DBUtils.close(rs, ps, conn);
        }
    }

    @Override
    public int insertUser(User user) {
        try {
            conn = DBUtils.getConn();
            String sql = "insert into user VALUES(null,?,?,?,?)";
            ps = conn.prepareStatement(sql);
            ps.setString(1, user.getUserName());
            ps.setString(2,user.getUserAge());
            ps.setString(3,user.getUserSex());
            ps.setString(4,user.getUserTel());
            int i = ps.executeUpdate();
            return i;
        } catch (SQLException e) {
            e.printStackTrace();
            return 0;
        } finally {
            DBUtils.close(rs, ps, conn);
        }
    }

    @Override
    public List selectUserById(String userName) {
        try {
            conn = DBUtils.getConn();
            String sql = "select * from user where user_name=?";
            ps = conn.prepareStatement(sql);
            ps.setString(1, userName);
            rs = ps.executeQuery();
            ArrayList users = new ArrayList<>();
            while(rs.next()) {
                User user = new User();
                user.setId(rs.getInt("id"));
                user.setUserName(rs.getString("user_name"));
                user.setUserAge(rs.getString("user_age"));
                user.setUserSex(rs.getString("user_sex"));
                user.setUserTel(rs.getString("user_tel"));
                users.add(user);
            }
            return users;
        } catch (SQLException e) {
            e.printStackTrace();
            return null;
        } finally {
            DBUtils.close(rs, ps, conn);
        }
    }

    @Override
    public int enrollUser(Administrator administrator) {
        try {
            conn = DBUtils.getConn();
            String sql = "insert into administrator VALUES(null,?,?)";
            ps = conn.prepareStatement(sql);
            ps.setString(1, administrator.getUserName());
            ps.setString(2,administrator.getUserPwd());
            int i = ps.executeUpdate();
            return i;
        } catch (SQLException e) {
            e.printStackTrace();
            return 0;
        } finally {
            DBUtils.close(rs, ps, conn);
        }
    }

    @Override
    public Administrator selectEnrollUser(Administrator administrator) {
        try {
            conn = DBUtils.getConn();
            String sql = "select * from administrator where user_name = ? and user_Pwd = ?";
            ps = conn.prepareStatement(sql);
            ps.setString(1,administrator.getUserName());
            ps.setString(2,administrator.getUserPwd());
            rs = ps.executeQuery();
            if (rs.next()){
                Administrator administrator1 = new Administrator();
                administrator1.setUserName(rs.getString("user_name"));
                administrator1.setUserPwd(rs.getString("user_pwd"));
                return administrator1;
            }
        } catch (SQLException e) {
            e.printStackTrace();
        }finally {
            DBUtils.close(rs,ps,conn);
        }
        return null;
    }

    @Override
    public int countUserAll() {
        try {
            conn =DBUtils.getConn();
            String sql="select count(*) as countAll from user";
            ps = conn.prepareStatement(sql);
            rs = ps.executeQuery();
            if(rs.next()){
                int count = rs.getInt("countAll");
                return count;
            }
        } catch (SQLException e) {
            e.printStackTrace();
        } finally {
            DBUtils.close(rs, ps, conn);
        }
        return 0;
    }

    @Override
    public List queryUserPage(int pageNum, int pageSize) {
        try {
            conn = DBUtils.getConn();
            String sql = "select * from user limit ?,?";
            ps = conn.prepareStatement(sql);
            ps.setInt(1,(pageNum-1)*pageSize);
            ps.setInt(2,pageSize);
            rs = ps.executeQuery();
            List users = new ArrayList<>();
            while (rs.next()){
                User user = new User();
                user.setId(rs.getInt("id"));
                user.setUserName(rs.getString("user_name"));
                user.setUserSex(rs.getString("user_sex"));
                user.setUserAge(rs.getString("user_age"));
                user.setUserTel(rs.getString("user_tel"));
                users.add(user);
            }
            return users;
        } catch (SQLException e) {
            e.printStackTrace();
            return null;
        } finally {
            DBUtils.close(rs,ps,conn);
        }

    }

    @Override
    public List searchUser(User user) {
        try {
            conn = DBUtils.getConn();
            String sql = "select * from user where 1=1 ";
            List params = new ArrayList<>();
            if(!(user.getUserName().equals("")||user.getUserName()==null)){
                sql+="and user_name = ?";
                params.add(user.getUserName());
            }

            if(!(user.getUserTel().equals("")||user.getUserTel()==null)){
                sql+="and user_tel = ?";
                params.add(user.getUserTel());
            }

            ps = conn.prepareStatement(sql);
            for (int i = 0; i  users = new ArrayList<>();
            while (rs.next()){
                User u = new User();
                u.setId(rs.getInt("id"));
                u.setUserName(rs.getString("user_name"));
                u.setUserSex(rs.getString("user_sex"));
                u.setUserAge(rs.getString("user_age"));
                u.setUserTel(rs.getString("user_tel"));
                users.add(u);
            }
            return users;
        } catch (SQLException throwables) {
            throwables.printStackTrace();
            return null;
        }finally {
            DBUtils.close(rs,ps,conn);
        }
    }
}
 

     

    utils 层  
     

    package com.hqyj.psl.utils;

import java.sql.*;

public class DBUtils {

    static {
        try {
            Class.forName("com.mysql.jdbc.Driver");
        } catch (ClassNotFoundException e) {
            e.printStackTrace();
        }
    }
    public static Connection getConn() throws SQLException {
        return DriverManager.getConnection("jdbc:mysql:///javaweb?characterEncoding=utf-8","root","root");
    }
    public static void close(ResultSet rs,PreparedStatement ps,Connection conn){
        if (rs!=null){
            try {
                rs.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }
        if (ps!=null){
            try {
                ps.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }
        if (conn!=null){
            try {
                conn.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }
    }
}

     

    package com.hqyj.psl.utils;

import java.util.List;

public class PageUtil {
    private int pageNum;
    private int passSize;
    private int totalCount;
    private List pageInfo;

    public int getPageNum() {
        return pageNum;
    }

    public void setPageNum(int pageNum) {
        this.pageNum = pageNum;
    }

    public int getPassSize() {
        return passSize;
    }

    public void setPassSize(int passSize) {
        this.passSize = passSize;
    }

    public int getTotalCount() {
        return totalCount;
    }

    public void setTotalCount(int totalCount) {
        this.totalCount = totalCount;
    }

    public List getPageInfo() {
        return pageInfo;
    }

    public void setPageInfo(List pageInfo) {
        this.pageInfo = pageInfo;
    }
}

     

     

    entity层 
     

    package com.hqyj.psl.entity;

public class Administrator {
    private int id;
    private String userName;
    private String userPwd;

    public Administrator(int id, String userName, String userPwd) {
        this.id = id;
        this.userName = userName;
        this.userPwd = userPwd;
    }

    public Administrator() {
    }

    @Override
    public String toString() {
        return "administrotar{" +
                "id=" + id +
                ", userName='" + userName + ''' +
                ", userPwd='" + userPwd + ''' +
                '}';
    }

    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }

    public String getUserName() {
        return userName;
    }

    public void setUserName(String userName) {
        this.userName = userName;
    }

    public String getUserPwd() {
        return userPwd;
    }

    public void setUserPwd(String userPwd) {
        this.userPwd = userPwd;
    }
}

     

     

    package com.hqyj.psl.entity;

public class User {
    private int id;
    private String userName;
    private String userAge;
    private String userSex;
    private String userTel;

    public User() {
    }

    public User(int id, String userName, String userAge, String userSex, String userTel) {
        this.id = id;
        this.userName = userName;
        this.userAge = userAge;
        this.userSex = userSex;
        this.userTel = userTel;
    }

    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }

    public String getUserName() {
        return userName;
    }

    public void setUserName(String userName) {
        this.userName = userName;
    }

    public String getUserAge() {
        return userAge;
    }

    public void setUserAge(String userAge) {
        this.userAge = userAge;
    }

    public String getUserSex() {
        return userSex;
    }

    public void setUserSex(String userSex) {
        this.userSex = userSex;
    }

    public String getUserTel() {
        return userTel;
    }

    public void setUserTel(String userTel) {
        this.userTel = userTel;
    }

    @Override
    public String toString() {
        return "User{" +
                "id=" + id +
                ", userName='" + userName + ''' +
                ", userAge='" + userAge + ''' +
                ", userSex='" + userSex + ''' +
                ", userTel='" + userTel + ''' +
                '}';
    }
}

     

     

    filter 层
     

    package com.hqyj.psl.Filter;

import javax.servlet.*;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import java.io.IOException;

public class CodeFilter implements Filter {
    @Override
    public void init(FilterConfig filterConfig) throws ServletException {

    }

    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        HttpServletRequest req = (HttpServletRequest)servletRequest;
        HttpServletResponse resp = (HttpServletResponse)servletResponse;
        req.setCharacterEncoding("UTF-8");
        resp.setContentType("text/html;charset=utf-8");
        filterChain.doFilter(req,resp);
    }

    @Override
    public void destroy() {

    }
}

     

     

    package com.hqyj.psl.Filter;

import javax.servlet.*;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import java.io.IOException;

public class LoginFilter implements Filter {
    @Override
    public void init(FilterConfig filterConfig) throws ServletException {

    }

    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        HttpServletRequest req = (HttpServletRequest)servletRequest;
        HttpServletResponse resp = (HttpServletResponse)servletResponse;
        String requestURI = req.getRequestURI();
        if (requestURI.endsWith("login1.jsp")||requestURI.endsWith("login")||requestURI.endsWith("login.jsp")||requestURI.contains("jpg")){
//            System.out.println(requestURI+"  sssss");
            filterChain.doFilter(req,resp);
        }else {
            HttpSession session = req.getSession();
            String name =(String) session.getAttribute("name");
            System.out.println(name);
            if (name!=null){
//                System.out.println(name);
                filterChain.doFilter(req,resp);
            }else {
//                System.out.println("........");
                req.getRequestDispatcher("./login.jsp").forward(req,resp);
            }
        }
    }

    @Override
    public void destroy() {

    }
}

     

     

    web.xml中的配置   编码过滤以及登录过滤
     

    



    
        CodeFilter
        com.hqyj.psl.Filter.CodeFilter
    
    
        CodeFilter
        /*
    

    
        LoginFilter
        com.hqyj.psl.Filter.LoginFilter
    
    
        LoginFilter
        /*
    


     

    
总结 

    该文章上传了核心代码，部分类的的定义以及接口没有上传，可以从实现类中看出
     

     小编也是小白，如有错误，请提出意见，互相进步。
     

    有问题请评论哦！
    


    

    

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