springboot集成mybatis

1.引入依赖。idea注意在build里面添加插件（idea默认不会扫面src里面xml文件）

<dependency>
    <groupId>org.mybatis.spring.boot</groupId>
    <artifactId>mybatis-spring-boot-starter</artifactId>
    <version>2.1.2</version>
</dependency>
<dependency>
    <groupId>org.projectlombok</groupId>
    <artifactId>lombok</artifactId>
    <optional>true</optional>
</dependency>
<dependency>
    <groupId>mysql</groupId>
    <artifactId>mysql-connector-java</artifactId>
</dependency>

<resources>
    <resource>
        <directory>src/main/java</directory>
        <includes>
            <include>**/*.xml</include>
        </includes>
    </resource>
</resources>

2.配置数据连接，开启mybatis

server:
  port: 80
  servlet:
    context-path: /mybatis

spring:
  datasource:
    driver-class-name: com.mysql.cj.jdbc.Driver
    url: jdbc:mysql://127.0.0.1:3307/luckymoney?serverTimezone=UTC
    username: root
    password: J*7fiFW1$4wB%5rl
  jpa:
    show-sql: true
mybatis:
  mapper-locations: com.zhangchao.mybatis.mapper/UserMapper.xml                   #resource文件夹下面mapper.xml路径
  type-aliases-package: com.zhangchao.mybatis.mapper             #mapper.xml文件中resultMap的type或者parameterType会使用自定义的pojo，这里是让mybatis自动扫描自定义pojo包(就是mapper.java)

3.编辑mapper.xml和mapper.java接口文件，注意：两文件同名，xml里面namespace=mapper.java的路径 。xml里面的id=mapper.java里面的接口名称

<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"  "http://mybatis.org/dtd/mybatis-3-mapper.dtd">

<mapper namespace="com.zhangchao.mybatis.mapper.UserMapper">
    <resultMap id="BaseResultMap" type="com.zhangchao.mybatis.Entity.User">
        <result column="id" jdbcType="VARCHAR" property="id" />
        <result column="name" jdbcType="VARCHAR" property="name" />
        <result column="age" jdbcType="INTEGER" property="age" />
        <result column="gender" jdbcType="INTEGER" property="gender" />
    </resultMap>
    <select id="getUserList" resultMap="BaseResultMap">
    select * from user
  </select>

</mapper>

package com.zhangchao.mybatis.mapper;


import com.zhangchao.mybatis.Entity.User;
import org.apache.ibatis.annotations.Mapper;

import java.util.List;

@Mapper
public interface UserMapper {
    List<User> getUserList();
}

4.等待被调用

package com.zhangchao.mybatis.controller;

import com.zhangchao.mybatis.Entity.User;
import com.zhangchao.mybatis.service.serviceImpl.UserServiceImpl;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RestController;

import java.util.List;

@RestController
public class UserController {
    @Autowired
    private UserServiceImpl service;

    @PostMapping("/getUserList")
    public List<User> getUserList(){
        return service.getUserList();
    }
}

package com.zhangchao.mybatis.service.serviceImpl;

import com.zhangchao.mybatis.Entity.User;
import com.zhangchao.mybatis.mapper.UserMapper;
import com.zhangchao.mybatis.service.UserService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import java.util.List;

@Service
public class UserServiceImpl implements UserService {
    @Autowired
    private UserMapper user;

    @Override
    public List<User> getUserList() {
        return user.getUserList();
    }
}

代码结构图