1.环境搭建

1.创建项目

2.编辑pom.xml文件

<properties>
        <java.version>1.8</java.version>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
        <spring-boot.version>2.4.1</spring-boot.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <!--mybatis依赖包-->
        <dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
            <version>2.2.0</version>
        </dependency>

        <!--jdbc依赖包-->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
        </dependency>
        <!--支持热部署的包-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-devtools</artifactId>
        </dependency>
        <!--引入插件lombok 自动的set/get/构造方法插件  -->
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
    </dependencies>

    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-dependencies</artifactId>
                <version>${spring-boot.version}</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
        </dependencies>
    </dependencyManagement>

    <build><!--测试打包 发布-->
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>3.8.1</version>
                <configuration>
                    <source>1.8</source>
                    <target>1.8</target>
                    <encoding>UTF-8</encoding>
                </configuration>
            </plugin>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
                <version>2.4.1</version>
                <configuration>
                    <mainClass>com.jt.SpringbootDemo3mybatisApplication</mainClass>
                </configuration>
                <executions>
                    <execution>
                        <id>repackage</id>
                        <goals>
                            <goal>repackage</goal>
                        </goals>
                    </execution>
                </executions>
            </plugin>
        </plugins>
    </build>

?3.复制之前项目src目录

?4.统一端口号

?5.导入前端项目

6.如何访问的登录页面

如何实现的？？？?用户发起请求http://localhost:8080(根路径)?

?最终看到html登录页面（已被Vue渲染完成的页面）

7.关于axios

?子组件使用的格式：this.$http

2.完成用户登录

?业务接口文档

2.1编辑SysResult对象（VO层）

vo：前后端进行数据交互的媒介

package com.jt.vo;

import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;
import lombok.experimental.Accessors;

@Data
@Accessors(chain = true)
@NoArgsConstructor
@AllArgsConstructor
public class SysResult {
    private Integer status;//200表示正常 201表示失败
    private String msg;    //服务器返回的提示信息
    private Object data;   //服务器返回的业务数据

    /*重载规则：参数不要耦合，否则会产生歧义*/
    public static SysResult fail(){
        return new SysResult(201,"服务调用失败",null);
    }
    public static SysResult sucess(Object data){
        return new SysResult(200,"服务调用成功",data);
    }
    public static SysResult sucess(String msg,Object data){
        return new SysResult(200,msg,data);
    }
}

2.2业务流程

2.2.1用户输入用户名与密码

2.2.2通过Vue的axios发起post请求

2.2.3Controller接收请求需要将密码进行加密处理

2.2.4查询成功则输入正确

登陆成功，返回token密钥，利用SysResult对象返回

2.2.5查询失败则输入有误

2.3 MD5

特点：只能由明文加密为密文，不可逆，不可破解

升级版本：MD5Hash=明文+盐值? 几乎不可破解

Controller层

package com.jt.controller;

import com.jt.pojo.User;
import com.jt.service.UserService;
import com.jt.vo.SysResult;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.*;

import java.util.List;

@RestController
@CrossOrigin
@RequestMapping("user")
public class UserController {


    @Autowired
    private UserService userService;

    @GetMapping("/findAll")
    public List<User> findAll(){

        return userService.findAll();
    }
    /*根据userName与password查询数据库
    * 类型post
    * 返回值SysResult
    * */
    @PostMapping("login")
    public SysResult login(@RequestBody User user){
        String token=userService.findUserByUP(user);
        //表示用户名和密码错误
        if(token==null||"".equals(token)){
            return SysResult.fail();
        }
        //表示用户名与密码正确，返回密钥信息
        return SysResult.sucess(token);
    }
}

Service层

package com.jt.service;

import com.jt.mapper.UserMapper;
import com.jt.pojo.User;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.util.DigestUtils;

import java.nio.charset.StandardCharsets;
import java.util.List;
import java.util.UUID;

@Service
public class UserServiceImpl implements UserService{

    @Autowired
    private UserMapper userMapper;


    @Override
    public List<User> findAll() {
        return userMapper.findAll();
    }

    //根据u/p查询数据库
    @Override
    public String findUserByUP(User user) {
//        1.将密码加密
        byte[] bytes = user.getPassword().getBytes();
        String md5Pass = DigestUtils.md5DigestAsHex(bytes);
        user.setPassword(md5Pass);
        //2.根据用户名和密文查询数据库
        User userDB = userMapper.findUserByUP(user);
        //3.判断userDB是否有值
        if(userDB == null){
            //查询没有数据.返回null
            return null;
        }
        //密钥特点：唯一性、迷惑性  UUID几乎可以保证唯一性
        return UUID.randomUUID().toString().replace("-","");
    }
}