SpringBoot学习之实现登录注册功能

偏执的太偏执、 2022-12-12 04:50 237阅读 0赞

1、系统目录结构

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2xpX3dfY2g_size_16_color_FFFFFF_t_70][]

2、创建数据库

数据库名称:student，数据表:user，创建命令如下：

//创建数据库
    create database student;
    
    //选择创建好的数据库，建立user表
    use student;
    
    create table user(
        id int primary key auto_increment,
        username varchar(32) unique not null,
        password varchar(32) not null
    );
    
    
    //想创建好的数据库中添加数据
    insert into user values(1,"xioming","000");
    
    //查看自己添加的数据
    select * from user;

3、创建前端页面

3.1 登录页面：login.html

<!DOCTYPE html>
    <html lang="en">
    <head>
        <meta charset="UTF-8">
        <title>login</title>
    </head>
    <body>
        <form method="post" action="/user/login">
            用户名：<input name="username" type="text"/>
            密码：<input name="password" type="password"/>
            <input type="submit" value="登录验证">
            <input type="button" onclick="javascript:window.location.href='regist.html'" value="去注册页面">
        </form>
    </body>
    </html>

3.2 注册页面：regist.html

<!DOCTYPE html>
    <html lang="en">
    <head>
        <meta charset="UTF-8">
        <title>regist</title>
    </head>
    <body>
        <form method="post" action="/user/regist">
            用户名：<input name="username" type="text"/>
            密码：<input name="password" type="password"/>
            <input type="submit" value="注册校验">
            <input type="button" onclick="javascript:window.location.href='login.html'" value="返回注册页面">
    
        </form>
    </body>
    </html>

4、Java代码

4.1 pom树

<?xml version="1.0" encoding="UTF-8"?>
    <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
             xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
        <modelVersion>4.0.0</modelVersion>
        <parent>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-parent</artifactId>
            <version>2.3.4.RELEASE</version>
            <relativePath/> 
        </parent>
        <groupId>com.example</groupId>
        <artifactId>studentsys</artifactId>
        <version>0.0.1-SNAPSHOT</version>
        <name>studentsys</name>
        <description>Demo project for Spring Boot</description>
    
        <properties>
            <java.version>11</java.version>
        </properties>
    
        <dependencies>
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter-jdbc</artifactId>
            </dependency>
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter-web</artifactId>
            </dependency>
            <dependency>
                <groupId>org.mybatis.spring.boot</groupId>
                <artifactId>mybatis-spring-boot-starter</artifactId>
                <version>2.1.3</version>
            </dependency>
    
            <dependency>
                <groupId>mysql</groupId>
                <artifactId>mysql-connector-java</artifactId>
                <scope>runtime</scope>
            </dependency>
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter-test</artifactId>
                <scope>test</scope>
                <exclusions>
                    <exclusion>
                        <groupId>org.junit.vintage</groupId>
                        <artifactId>junit-vintage-engine</artifactId>
                    </exclusion>
                </exclusions>
            </dependency>
            <dependency>
                <groupId>org.projectlombok</groupId>
                <artifactId>lombok</artifactId>
            </dependency>
    
            <dependency>
                <groupId>com.alibaba</groupId>
                <artifactId>fastjson</artifactId>
                <version>1.2.73</version>
            </dependency>
    
        </dependencies>
    
        <build>
            <plugins>
                <plugin>
                    <groupId>org.springframework.boot</groupId>
                    <artifactId>spring-boot-maven-plugin</artifactId>
                </plugin>
            </plugins>
        </build>
    
    </project>

4.2 数据配置信息：application.properties

#配置数据库连接信息
    spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver
    spring.datasource.url=jdbc:mysql://localhost:3306/student?characterEncoding=utf-8&serverTimezone=UTC
    spring.datasource.username=root
    spring.datasource.password=root
    
    #数据库连接池
    
    #mapper映射
    mybatis.type-aliases-package=com.example.studentsys.entiy
    mybatis.mapper-locations=classpath:mapper/*.xml

4.3 实体类：User.java

package com.example.studentsys.entiy;
    
    public class User {
        private Integer id;
        private String username;
        private String password;
    
        public void setId(Integer id){
            this.id = id;
        }
        public Integer getId(){
            return id;
        }
        public void setUsername(String username){
            this.username = username;
        }
        public String getUsername(){
            return username;
        }
        public void setPassword(String password){
            this.password = password;
        }
        public String getPassword(){
            return password;
        }
    }

4.4  mapper接口：UserMapper.java

package com.example.studentsys.mapper;
    
    import com.example.studentsys.entiy.User;
    import org.apache.ibatis.annotations.Mapper;
    import org.springframework.stereotype.Repository;
    
    import java.util.List;
    
    //@Repository将类标识为bean
    @Repository
    @Mapper
    public interface UserMapper {
        List<User> findAll();
        User findByName(String name);
        String findPswByName(String UserName);
        void save(User user);
    }

4.5  UserMapper.xml

<?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.example.studentsys.mapper.UserMapper">
        <select id="findAll" resultType="User">
            select * from User
        </select>
        <select id="findByName" resultType="User">
            select * from User where username=#{username}
        </select>
        <select id="findPswByName" resultType="String">
            select password from user where username = #{username}
        </select>
        <insert id="save">
            insert into user(username,password) value (#{username},#{password})
        </insert>
    </mapper>

4.6 service类：UserService.java

package com.example.studentsys.service;
    
    import com.alibaba.fastjson.JSON;
    import com.alibaba.fastjson.JSONObject;
    import com.example.studentsys.entiy.User;
    import com.example.studentsys.mapper.UserMapper;
    import org.apache.ibatis.jdbc.Null;
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.stereotype.Service;
    
    import java.util.Collections;
    import java.util.List;
    
    @Service
    public class UserService {
    
        //该注解可以对类成员变量、方法以及构造函数进行标注，完成自动装配工作
        @Autowired
        UserMapper userMapper;
    
        public String login(User user){
            //登录逻辑函数
            try{
                User userExistN = userMapper.findByName(user.getUsername());
                if(userExistN!=null){
                    String userExistP = userMapper.findPswByName(user.getUsername());
                    if(userExistP.equals(user.getPassword())){
                        return user.getUsername()+"登录成功，欢迎您!";
                    }else {
                        return "登录失败，密码错误!";
                    }
                }else {
                    return "登录失败，用户不存在!";
                }
            }catch (Exception e){
                e.printStackTrace();
                return e.getMessage();
            }
        }
    
        public String regist(User user){
            //注册逻辑函数
            try {
                User userExist = userMapper.findByName(user.getUsername());
                if (user.getUsername().equals("")){
                    return "用户名不能为空";
                }else if (user.getPassword().equals("")){
                    return "密码不能为空";
                }else if (userExist!=null){
                    return "账户已经存在";
                }else{
                    userMapper.save(user);
                    return "注册成功";
                }
            }catch (Exception e){
                e.printStackTrace();
                return e.getMessage();
            }
    
        }
    
        public List<User> findAll(){
            List<User> list = userMapper.findAll();
            return list;
        }
    
    }

4.7  控制类：UserController.java

package com.example.studentsys.controller;
    
    import com.example.studentsys.entiy.User;
    import com.example.studentsys.service.UserService;
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.web.bind.annotation.PostMapping;
    import org.springframework.web.bind.annotation.RequestMapping;
    import org.springframework.web.bind.annotation.RequestMethod;
    import org.springframework.web.bind.annotation.RestController;
    
    import java.util.List;
    
    @RestController
    @RequestMapping("/user")
    public class UserController {
        @Autowired
        UserService userService;
    
        @PostMapping("/login")
        public String login(User user){
            return userService.login(user);
        }
    
        @PostMapping("/regist")
        public String regist(User user){
            return userService.regist(user);
        }
    
        /**
         * 解决查询数据库中文出现乱码问题
         * @return
         */
        @RequestMapping(value = "/alluser", method = RequestMethod.GET, produces = "application/json;charset=UTF-8")
        public List<User> findAll(){
            return userService.findAll();
        }
    }

5、运行项目

http://localhost:8080/login.html 进入到登录页面

http://localhost:8080/regist.html 进入到注册页面

http://localhost:8080/user/alluser 查看当前所有用户信息

6、总结

[MySQL常见管理命令][MySQL]

[@RestController注解][RestController]

业务逻辑：

Mapper负责连接数据并进行相关的CRUD操作

Service借助Mapper来完成登录注册的业务逻辑

Controller接待浏览器访问，借助Service提供登录注册服务

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[MySQL]: https://blog.csdn.net/li_w_ch/article/details/108469043
[RestController]: https://blog.csdn.net/li_w_ch/article/details/108937337