（MVC）SpringBoot+Mybatis+Mapper.xml

前言：本篇博客主要对MVC架构、Mybatis工程加深下理解，前面写过一篇博客：SprintBoot+html/css/js+mybatis的demo，里面涉及到了Mybatis的应用，此篇博客主要介绍一种将sql语句写到了配置文件里的方法，即Mybatis里Mapper.xml文件配置，其主要用于定义sql语句和映射关系

MVC架构流程图

配置文件

mapper层

model层

service层

controller层

结果展示

MVC架构流程图

根据自己的理解画了一下访问接口时，涉及到service层、mapper层、mybatis工程的应用

上篇博客地址：

https://blog.csdn.net/MRJJ_9/article/details/131884585

配置文件

xml配置文件

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapperPUBLIC "-//mybatis.org//DTD Mapper 3.0//EN""http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<!-- namespace:填写映射当前的Mapper接口，所有的增删改查的参数和返回值类型，就可以直接填写缩写，不区分大小写，直接通过方法名去找类型-->
<mapper namespace="com.example.interfaceautotest.mapper.CaseMapper">
<!--    id 对应的是mapper.CaseMapper里的方法名--><select id="getInfoByPhone" resultType="com.example.interfaceautotest.model.MysqlUserData">select * from user where phone =#{phone} and pw =#{pw}  </select></mapper>

在application.properties文件里完成对应的配置

spring.datasource.url=jdbc:mysql://localhost:3306/auto_test_data?useUnicode=true&characterEncoding=utf8&serverTimezone=UTC
spring.datasource.username=root
spring.datasource.password=123456
mybatis.mapper-locations=classpath:/mapper/*.xml

mapper层

mapper里的方法

package com.example.interfaceautotest.mapper;import com.example.interfaceautotest.model.MysqlUserData;
import org.apache.ibatis.annotations.Mapper;
import org.apache.ibatis.annotations.Param;@Mapper
public interface CaseMapper {MysqlUserData getInfoByPhone(@Param("phone") String phone,@Param("pw") String pw);
}

model层

model层与数据库的关联

package com.example.interfaceautotest.model;//注册表
public class MysqlUserData{private String id;private String usr;private String pw;private String phone;private String email;public String getId(){return id;}public void setId(String id){this.id = id;}public String getUsr(){return usr;}public void setUsr(String usr){this.usr = usr;}public String getPw(){return pw;}public void setPw(String pw){this.pw = pw;}public String getPhone(){return phone;}public void setPhone(String phone){this.phone = phone;}public String getEmail(){return email;}public void setEmail(String email){this.email = email;}}

model层与service层关联的返回结果

package com.example.interfaceautotest.model;import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;@Data
@AllArgsConstructor
@NoArgsConstructor
public class Result {public int code;public String msg;public Object data;public int getCode(){return code;}public void setCode(int code){this.code = code;}public String getMsg(){return msg;}public void setMsg(String msg){this.msg = msg;}public Object getData(){return data;}public void setData(Object data){this.data = data;}
}

service层

package com.example.interfaceautotest.service.impl;import com.example.interfaceautotest.mapper.CaseMapper;
import com.example.interfaceautotest.model.MysqlUserData;
import com.example.interfaceautotest.model.Result;
import com.example.interfaceautotest.service.UserService;
import org.springframework.stereotype.Service;import javax.annotation.Resource;@Service("UserSevice")
public class UserServiceImpl implements UserService {@ResourceCaseMapper CaseMapper;public Result login(String username, String password) {if (username == null || password == null)return new Result(-1,"用户名或密码不能为空","用户名或密码不能为空");MysqlUserData user = CaseMapper.getInfoByPhone(username, password);if (user==null){return new Result(-3,"用户名或密码错误","用户名或密码错误");}else {return new Result(1,"登录成功",user);}}
}

controller层

package com.example.interfaceautotest.controller;
import com.example.interfaceautotest.model.Result;
import com.example.interfaceautotest.service.UserService;
import org.springframework.web.bind.annotation.*;import javax.annotation.Resource;@RestController
@RequestMapping("/test")
public class Login {@ResourceUserService UserService;@GetMapping("/login")public Result login(String username, String password){return UserService.login(username,password);}}