在线教育项目-day05【课程分类管理-添加课程分类】

1.引入依赖

之前测试EasyExcel已经引入过了

2.利用代码生成器生成结构

我们做的只需要更改代码生成器的数据库表即可

3.运行代码生成器

4.书写代码

1.controller

@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();
    }

}

2.service

@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);
}

3.serviceImpl

@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();
        }

    }
}

4.Excel实体类

@Data
public class SubjectData {
    @ExcelProperty(index=0)
    private String oneSubjectName;
    @ExcelProperty(index=1)
    private String secondSubjectName;

}

5.

最后关于这个监听器,我们要注意一个问题,因为代码的原因我们没法把监听器交给Spring管理

所以要把eduSujectService传进来

5.书写监听器

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;
    }
}