依赖

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

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

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

        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>5.1.39</version>
        </dependency>

        <dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
            <version>1.1.1</version>
        </dependency>

        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <version>1.18.6</version>
            <optional>true</optional>
        </dependency>

实体类（entity）

Course

package com.springboot.mybatis.controller;

import com.springboot.mybatis.entity.Course;
import com.springboot.mybatis.service.CourseService;
import com.springboot.mybatis.util.RandomUtil;
import org.springframework.web.bind.annotation.*;

import javax.annotation.Resource;
import java.util.List;

@RestController
@RequestMapping(value = "/api")
public class CourseController {
    @Resource
    private CourseService courseService;

    @RequestMapping(value = "/courses",method = RequestMethod.GET)
    public List<Course> selectAll(){
        return courseService.selectAll();
    }

    @RequestMapping(value = "/course/{id}",method = RequestMethod.GET)
    public Course getOne(@PathVariable("id") long id){
        return courseService.getOne(id);
    }

    @RequestMapping(value = "/course/{id}",method = RequestMethod.DELETE)
    public void delete(@PathVariable("id") long id){
        courseService.delete(id);
    }
    @RequestMapping(value = "/course",method = RequestMethod.POST)
    public Course addCourse(@RequestBody Course course){
        course.setCourseCode(RandomUtil.getRandomCode());
        return courseService.insert(course);
    }

}

mapper

CourseMapper

package com.springboot.mybatis.mapper;

import com.springboot.mybatis.entity.Course;
import org.apache.ibatis.annotations.*;

import java.util.List;

public interface CourseMapper {


    @Results({
            @Result(column = "course_id", property = "courseId"),
            @Result(column = "course_name", property = "courseName"),
            @Result(column = "user_id", property = "userId"),
            @Result(column = "course_class", property = "courseClass"),
            @Result(column = "cover", property = "cover"),
            @Result(column = "course_code", property = "courseCode"),
            @Result(column = "finished", property = "finished"),
    })
    @Select("select * from t_course")
    List<Course> selectAll();


    @Results({
            @Result(column = "course_id", property = "courseId"),
            @Result(column = "course_name", property = "courseName"),
            @Result(column = "user_id", property = "userId"),
            @Result(column = "course_class", property = "courseClass"),
            @Result(column = "cover", property = "cover"),
            @Result(column = "course_code", property = "courseCode"),
            @Result(column = "finished", property = "finished"),
    })
    @Select("select * from t_course where course_id = #{courseId}")
    Course getOne(Long courseId);

    @Delete("DELETE FROM t_course WHERE course_id =#{courseId}")
    void delete(Long courseId);

    @Insert("INSERT INTO t_course(course_name,user_id,course_class,cover,course_code,finished) VALUES(#{courseName},#{userId},#{courseClass},#{cover},#{courseCode},#{finished})")
    void insert(Course course);

    @Update("UPDATE t_course SET course_name= #{courseName},cover= #{cover},finished=#{finished}")
    void update(Course course);

}

Service

CourseService

package com.springboot.mybatis.service;

import com.springboot.mybatis.entity.Course;

import java.util.List;

public interface CourseService {
    List<Course> selectAll();

    Course getOne(Long courseId);

    void delete(long courseId);

    Course insert(Course course);

    void update(Course course);
}

impl

CourseServiceImpl

package com.springboot.mybatis.service.Impl;

import com.springboot.mybatis.entity.Course;
import com.springboot.mybatis.mapper.CourseMapper;
import com.springboot.mybatis.service.CourseService;
import org.springframework.stereotype.Service;

import javax.annotation.Resource;
import java.util.List;

@Service
public class CourseServiceImpl implements CourseService {
    @Resource
    private CourseMapper courseMapper;

    @Override
    public List<Course> selectAll() {
        return courseMapper.selectAll();
    }

    @Override
    public Course getOne(Long courseId) {
        return courseMapper.getOne(courseId);
    }
    @Override
    public void delete(long courseId){
        courseMapper.delete(courseId);
    }

    @Override
    public Course insert(Course course) {
        courseMapper.insert(course);
        return course;
    }

    @Override
    public void update(Course course){
        courseMapper.update(course);
    }

}

controller

CourseController

package com.springboot.mybatis.controller;

import com.springboot.mybatis.entity.User;
import com.springboot.mybatis.service.UserService;
import org.springframework.web.bind.annotation.*;

import javax.annotation.Resource;
import java.util.List;

@RestController
@RequestMapping(value = "/API")
public class UserController {

    @Resource
    private UserService userService;

    @RequestMapping(value = "/users",method = RequestMethod.GET)
    public List<User> selectAll(){
        return userService.selectAll();
    }

    @RequestMapping(value = "/user/{id}",method = RequestMethod.GET)
    public User getOne(@PathVariable("id") long id){
        return userService.getOne(id);
    }

    @RequestMapping(value = "/user/{id}",method = RequestMethod.DELETE)
    public void delete(@PathVariable("id") long id){
        userService.delete(id);
    }

    @RequestMapping(value = "/user",method = RequestMethod.POST)
    public void addUser(@RequestBody User user){
        userService.insert(user);
    }

    @RequestMapping(value = "/user",method = RequestMethod.PUT)
    public void updateUser(@RequestBody User user){
        userService.update(user);
    }
}

测试类

package com.springboot.mybatis.service.Impl;

import com.springboot.mybatis.entity.Course;
import com.springboot.mybatis.service.CourseService;
import com.springboot.mybatis.util.RandomUtil;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.test.context.junit4.SpringRunner;

import javax.annotation.Resource;
import java.util.List;


@RunWith(SpringRunner.class)
@SpringBootTest
public class CourseServiceImplTest {

    @Resource
    private CourseService courseService;

    @Test
    public void selectAll() {
        List<Course> courseList = courseService.selectAll();
        courseList.forEach(course -> System.out.println(course));
    }

    @Test
    public void getOne() {
        Course course = courseService.getOne(1L);
        System.out.println(course);
    }


    @Test
    public void delete() {
        courseService.delete(5L);
    }

    @Test
    public void insert(){
        Course course=new Course();
        course.setCourseName("微信开发小程序");
        course.setCourseClass("软件1721");
        course.setUserId(1L);
        course.setCover("1.jpg");
        course.setCourseCode(RandomUtil.getRandomCode());
        course.setFinished((short) 0);
        courseService.insert(course);
    }
    @Test
    public void update(){
        Course course=courseService.getOne(5L);
        course.setCourseName("js");
        course.setCover("123.jpg");
        course.setFinished((short)0);
        courseService.update(course);
    }


}