SpringBootJPA实现增删改查

@Entity
public class Grade {
    @Id
    @GeneratedValue(strategy= GenerationType.AUTO)
    private Integer grade_id;
    private String grade_name;

    public Integer getGrade_id() {
        return grade_id;
    }

    public void setGrade_id(Integer grade_id) {
        this.grade_id = grade_id;
    }

    public String getGrade_name() {
        return grade_name;
    }

    public void setGrade_name(String grade_name) {
        this.grade_name = grade_name;
    }
}

@Repository
public interface IGradeMapper extends CrudRepository<Grade,Integer> {
}

@RestController
@RequestMappng("/IGradeController")
public class IGradeController {
    @Resource
    private IGradeService iGradeService;
    
    //新增数据
    @RequestMapping("/insertGrade")
    public Grade insertGrade(){
        Grade grade=new Grade();
        grade.setGrade_name("S1");
        return iGradeService.insertGrade(grade);
    }

    @RequestMapping("/updateGrade")
    public Grade updateGrade(){
        Grade grade=new Grade();
        grade.setGrade_id(1);
        grade.setGrade_name("S2");
        return iGradeService.updateGrade(grade);
    }

    @RequestMapping("/deleteGrade")
    public void deleteGrade(){
        iGradeService.deleteGrade(1);
    }

    @RequestMapping("/getAllGrade")
    public Iterable<Grade> getAllGrade(){
       return  iGradeService.getAll();
    }
}

public interface IGradeService {
    public Grade insertGrade(Grade grade);
    
    public Grade updateGrade(Grade grade);

    public void deleteGrade(Integer id);
    
    public Iterable<Grade> getAll();
}

@Service("iGradeService")
public class IGradeServcieImpl implements IGradeService {
    @Resource
    private IGradeMapper iGradeMapper;
    
    @Override
    public Grade insertGrade(Grade grade) {
        return iGradeMapper.save(grade);
    }

    @Override
    public Grade updateGrade(Grade grade) {
        return iGradeMapper.save(grade);
    }

    @Override
    public void deleteGrade(Integer id) {
        iGradeMapper.delete(id);
    }

    @Override
    public Iterable<Grade> getAll() {
        return iGradeMapper.findAll();
    }
}

@SpringBootApplication
public class StartSpringBoot {
    public static void main(String[] args) {
        SpringApplication.run(StartSpringBoot.class,args);
    }
}