Develop a simple login logic based on SSM

Preface

We have learned before SSM Whole MyBatis-plus Integration of , In this section, we will use the integrated project to develop a simple login logic .

Learning content

New projects

1. stay IDEA Create a new normal maven project ;
   

2. Improve our engineering structure as follows , The subcontracting functions are shown in the figure ;
   

3. Introduce project dependencies , To configure MyBatis-Plus;
   Refer to the previous article ： Learn together Java——SSM Integration and MyBatis-Plus Use

4. Create a new user data table ;
   

Write project code

1. New entity class -User;

package com.five.study.entity;

import com.baomidou.mybatisplus.annotation.IdType;
import com.baomidou.mybatisplus.annotation.TableId;
import com.baomidou.mybatisplus.annotation.TableName;

/** * Description: * * @Author: kk( major bug Development ) * DateTime: 2022-02-15 16:58 */
@TableName("user")
public class User {
    
    @TableId(type= IdType.AUTO)
    private Long userId;
    private String username;
    private String password;
    private Integer salt;

    public Long getUserId() {
    
        return userId;
    }

    public void setUserId(Long userId) {
    
        this.userId = userId;
    }

    public String getUsername() {
    
        return username;
    }

    public void setUsername(String username) {
    
        this.username = username;
    }

    public String getPassword() {
    
        return password;
    }

    public void setPassword(String password) {
    
        this.password = password;
    }

    public Integer getSalt() {
    
        return salt;
    }

    public void setSalt(Integer salt) {
    
        this.salt = salt;
    }
}

2. newly build mapper Interface ;

package com.five.study.mapper;

import com.baomidou.mybatisplus.core.mapper.BaseMapper;
import com.five.study.entity.User;

/** * Description: * * @Author: kk( major bug Development ) * DateTime: 2022-02-15 17:03 */
public interface UserMapper extends BaseMapper<User> {
    
}

3. newly build user.xml file ;

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.five.study.mapper.UserMapper">

</mapper>

4. To write Service Interface ;

package com.five.study.service;

import com.five.study.entity.User;

/** * Description: * * @Author: kk( major bug Development ) * DateTime: 2022-02-15 17:08 */
public interface UserService {
    

    /** *  User registration , Create a new user  * * @param username  user name  * @param password  password  * @param nickname  nickname  * @return  New user object  */
    public User createUser(String username, String password, String nickname);

    /** *  Login check  * * @param username  user name  * @param password  password  * @return  Login object  */
    public User checkLogin(String username, String password);
}

5. newly build MD5 Encryption utility class ;

package com.five.study.utils;


import org.apache.commons.codec.digest.DigestUtils;

/** * Description: * * @Author: kk( major bug Development ) * DateTime: 2022-02-12 17:28 */
public class MD5Utils {
    
    public static String md5Digest(String source , Integer salt){
    
        char[] ca = source.toCharArray();
        // Obfuscate source data 
        for(int i = 0 ; i < ca.length ; i++){
    
            ca[i] = (char) (ca[i] + salt);
        }
        String target = new String(ca);
        String md5 = DigestUtils.md5Hex(target);
        return md5;
    }
}

6. To write Service Implementation class ;

package com.five.study.service.impl;

import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
import com.five.study.entity.User;
import com.five.study.mapper.UserMapper;
import com.five.study.service.UserService;
import com.five.study.service.exception.BussinessException;
import com.five.study.utils.MD5Utils;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;

import javax.annotation.Resource;
import java.util.Date;
import java.util.List;
import java.util.Random;

/** * Description: * * @Author: kk( major bug Development ) * DateTime: 2022-02-15 17:09 */
@Service("userService")
@Transactional
public class UserServiceImpl implements UserService {
    

    @Resource
    private UserMapper userMapper;
    /** *  User registration , Create a new user  * * @param username  user name  * @param password  password  * @param nickname  nickname  * @return  New user object  */
    public User createUser(String username, String password, String nickname) {
    
        QueryWrapper<User> queryWrapper = new QueryWrapper<User>();
        queryWrapper.eq("username", username);
        List<User> userList = userMapper.selectList(queryWrapper);
        // Determine whether the user name already exists 
        if(userList.size() > 0){
    
            throw new BussinessException("M01"," User name already exists ");
        }
        User user = new User();
        user.setUsername(username);
        int salt = new Random().nextInt(1000) + 1000; // Salt value 
        String md5 = MD5Utils.md5Digest(password, salt);
        user.setPassword(md5);
        user.setSalt(salt);
        userMapper.insert(user);
        return user;
    }

    /** *  Login check  * * @param username  user name  * @param password  password  * @return  Login object  */
    public User checkLogin(String username, String password){
    
        QueryWrapper<User> queryWrapper = new QueryWrapper<User>();
        queryWrapper.eq("username", username);
        User user = userMapper.selectOne(queryWrapper);
        if(user == null){
    
            throw new BussinessException("M02", " The user doesn't exist ");
        }
        String md5 = MD5Utils.md5Digest(password, user.getSalt());
        if(!md5.equals(user.getPassword())){
    
            throw new BussinessException("M03", " Wrong password ");
        }
        return user;
    }
}

6. To write Service Test class ;

package com.five.study.service.impl;

import com.five.study.service.UserService;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.test.context.ContextConfiguration;
import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;

import javax.annotation.Resource;

import static org.junit.Assert.*;

/** * Description: * * @Author: kk( major bug Development ) * DateTime: 2022-02-15 17:23 */
@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(locations = {
    "classpath:applicationContext.xml"})
public class UserServiceImplTest {
    
    @Resource
    private UserService userService;

    @Test
    public void createUser() {
    
        userService.createUser("admin", "123456");
    }

    @Test
    public void checkLogin() {
    
        userService.checkLogin("admin", "123456");
    }
}

test result ：


7. Write controller Controller;

package com.five.study.controller;

import com.five.study.entity.User;
import com.five.study.service.UserService;
import com.five.study.service.exception.BussinessException;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.ResponseBody;

import javax.annotation.Resource;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpSession;
import java.util.HashMap;
import java.util.Map;

/** * Description: * * @Author: kk( major bug Development ) * DateTime: 2022-02-15 17:39 */
@Controller
public class UserController {
    
    @Resource
    private UserService userService;

    /** *@Description:  Register a new user controller  *@Param: *@return: */
    @PostMapping("/registe")
    @ResponseBody
    public Map registe(String username, String password) {
    
        Map result = new HashMap();
        try {
    
            userService.createUser(username, password);
            result.put("code", "0");
            result.put("msg", "success");
        } catch (BussinessException ex) {
    
            ex.printStackTrace();
            result.put("code", ex.getCode());
            result.put("msg", ex.getMsg());
        }
        return result;
    }

    /** *@Description:  Log in to verify the controller  *@Param: *@return: */
    @PostMapping("/check_login")
    @ResponseBody
    public Map checkLogin(String username, String password) {
    

        Map result = new HashMap();

        try {
    
            User user = userService.checkLogin(username, password);
            result.put("code", "0");
            result.put("msg", "success");
        } catch (BussinessException ex) {
    
            ex.printStackTrace();
            result.put("code", ex.getCode());
            result.put("msg", ex.getMsg());
        }
        return result;
    }
}

8. To configure tomcat The server ;
   See article ： Learn together Java——IDEA Rapid development of web application

9. Use APIPost test ;
   
   

summary

Because I have just started using SSM Development , So the arrangement may not be in place , If you find a problem , Welcome to comment area ~