SpringBoot整合Mybatis

我们引入上一章节的Druid配置文件，并且建立两张表，如下所示：


当然，我们也可以写一个sql文件，再用深入理解springboot（5）的方法，也能得到同样的结果。

我们建立两个bean——>Department and Employee：

public class Department {

    private Integer d_id;
    private String d_name;

   ....省去get/set
}

public class Employee {
    private Integer id;
    private String lastname;
    private String email;
    private Integer gender;
    private Integer d_id;

    ....省去get/set
}

然后建立一个mapper.DepartmentMapper

@Mapper
public interface DepartmentMapper {
    @Select("select * from department where d_id=#{id}")
    public Department getDeptById(Integer id);

    @Delete("delete from department where d_id=#{id}")
    public int deleteDeptById(Integer id);

    @Options(useGeneratedKeys = true,keyProperty = "d_id")//告诉注解版的mybatis【department】对象中的id为自增主键
    @Insert("insert into department(d_id, d_name) values(#{d_id},#{d_name})")
    public int insertDept(Department department);

    @Update("update department set d_name=#{d_name} where d_id=#{d_id}")
    public int updateDept(Department department);
}

最后，再安排一个Controller.DeptController：

@RestController
public class DeptController {

    @Autowired
    DepartmentMapper departmentMapper;

    @GetMapping("/dept/{id}")
    public Department getDepartment(@PathVariable("id") Integer id){
        return departmentMapper.getDeptById(id);
    }

    @GetMapping("/dept")
    public Department insertDept(Department department){
        departmentMapper.insertDept(department);
        return department;
    }
}

当然，为了方便起见（其实也没方便什么！！），我们可以去掉@Mapper ，用一个@MapperScan加到启动类上面，相当于指定给 mapper包下面的所有的类都加上@Mapper一样，批量扫描所有的接口：

@MapperScan(value = "com.king.mybatis.mapper")
@SpringBootApplication
public class MybatisApplication {
    public static void main(String[] args) {
        SpringApplication.run(MybatisApplication.class, args);
    }
}

还有XML配置的方法，这个之前学过，就不再赘述。