<dependency>

            <groupId>org.mybatis.spring.boot</groupId>

            <artifactId>mybatis-spring-boot-starter</artifactId>

            <version>1.3.</version>

</dependency>

mybatis.mapper-locations=classpath:public/mybatis/mapper/*.xml

mybatis.config-location=classpath:public/mybatis/mybatis-config.xml

<?xml version="1.0" encoding="UTF-8" ?>

<!DOCTYPE configuration

        PUBLIC "-//mybatis.org//DTD Config 3.0//EN"

        "http://mybatis.org/dtd/mybatis-3-config.dtd">

<configuration>

    <settings>

        <setting name="mapUnderscoreToCamelCase" value="true"/>

    </settings>

</configuration>

<?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.atguigu.springBoot01.mapper.EmployeeMapper">

    <!-- public Employee getEmpById(Integer id); public void insertEmp(Employee

        employee); -->

    <resultMap type="com.atguigu.springBoot01.entity.Employee" id="empMap">

        <id column="id" property="id" />

        <result column="lastName" property="lastName" />

        <result column="email" property="email" />

        <result column="gender" property="gender" />

        <result column="department_id" property="department.id" />

    </resultMap>

    <select id="getEmpById" resultMap="empMap">

        SELECT * FROM t_employee WHERE id=#{id}

    </select>

    <insert id="insertEmp" parameterType="com.atguigu.springBoot01.entity.Employee">

        INSERT INTO t_employee(last_name,email,gender,department_id) VALUES

        (#{lastName},#{email},#{gender},#{department.id})

    </insert>

</mapper>

package com.atguigu.springBoot01.mapper;

import com.atguigu.springBoot01.entity.Employee;

public interface EmployeeMapper {

    public Employee getEmpById(Integer id);

    public void insertEmp(Employee emp);

}

@SpringBootApplication

@MapperScan(value = "com.atguigu.springBoot01.mapper")

public class Application {

    public static void main(String[] args) {

        SpringApplication.run(Application.class, args);

    }

}