@RestController

@CrossOrigin

@RequestMapping("/eduservice/edu-subject")

public class EduSubjectController {

    @Autowired

    private EduSubjectService eduSubjectService;

    //添加课程分类

    //获取上传的文件，把文件内容读出来

    @PostMapping("addSubject")

    public R addSubject(MultipartFile file){

        eduSubjectService.save(file);

        return R.OK();

    }

}

@Data

public class SubjectData {

    @ExcelProperty(index=0)

    private String oneSubjectName;

    @ExcelProperty(index=1)

    private String secondSubjectName;

}

public interface EduSubjectService extends IService<EduSubject> {

    //添加课程分类

    void save(MultipartFile file);

}

@Service

public class EduSubjectServiceImpl extends ServiceImpl<EduSubjectMapper, EduSubject> implements EduSubjectService {

    @Override

    public void save(MultipartFile file) {

        try {

            InputStream inputStream=file.getInputStream();

            EasyExcel.read(inputStream, SubjectData.class,new SubjectExcelsListener()).sheet().doRead();

        }catch (Exception e){

            e.printStackTrace();

        }

    }

}

@Data

public class SubjectData {

    @ExcelProperty(index=0)

    private String oneSubjectName;

    @ExcelProperty(index=1)

    private String secondSubjectName;

}

public class SubjectExcelsListener extends AnalysisEventListener<SubjectData> {

    public EduSubjectService subjectService;

    public SubjectExcelsListener(){}

    public SubjectExcelsListener(EduSubjectService subjectService){

        this.subjectService=subjectService;

    }

    //一行一行去读取excle内容

    @Override

    public void invoke(SubjectData subjectData, AnalysisContext analysisContext) {

        if(subjectData == null) {

            throw new onlineEduException(20001,"添加失败");

        }

        //添加一级分类

        EduSubject existOneSubject = this.existOneSubject(subjectService,subjectData.getOneSubjectName());

        if(existOneSubject == null) {//没有相同的

            existOneSubject = new EduSubject();

            existOneSubject.setTitle(subjectData.getOneSubjectName());

            existOneSubject.setParentId("0");

            subjectService.save(existOneSubject);

        }

        //获取一级分类id值

        String pid = existOneSubject.getId();

        //添加二级分类

        EduSubject existTwoSubject = this.existTwoSubject(subjectService,subjectData.getSecondSubjectName(), pid);

        if(existTwoSubject == null) {

            existTwoSubject = new EduSubject();

            existTwoSubject.setTitle(subjectData.getSecondSubjectName());

            existTwoSubject.setParentId(pid);

            subjectService.save(existTwoSubject);

        }

    }

    @Override

    public void doAfterAllAnalysed(AnalysisContext analysisContext) {

    }

    //判断一级分类是否重复

    private EduSubject existOneSubject(EduSubjectService subjectService,String name) {

        QueryWrapper<EduSubject> wrapper = new QueryWrapper<>();

        wrapper.eq("title",name);

        wrapper.eq("parent_id","0");

        EduSubject eduSubject = subjectService.getOne(wrapper);

        return eduSubject;

    }

    //判断二级分类是否重复

    private EduSubject existTwoSubject(EduSubjectService subjectService,String name,String pid) {

        QueryWrapper<EduSubject> wrapper = new QueryWrapper<>();

        wrapper.eq("title",name);

        wrapper.eq("parent_id",pid);

        EduSubject eduSubject = subjectService.getOne(wrapper);

        return eduSubject;

    }

}