element-ui upload 文件的Java 后端代码

把文件保存到S3对应的路径：

@PostMapping(value = "uploadFile")
public ResultUtil uploadFeedBack(MultipartHttpServletRequest request) {
    ResultUtil result = new ResultUtil();
    try {
        MultipartHttpServletRequest multipartRequest = request;
        SysUserFeedBackEntity userFeedBackEntity = new SysUserFeedBackEntity();
        //userFeedBackEntity 这个entity包含了页面的其他需要保存到数据的点，对于获取到file //multipartRequest.getFile("uploadFile0");
userFeedBackEntity.setCategoryId(Integer.valueOf(request.getParameter("categoryId")));
       
        userFeedBackEntity.setDescription(request.getParameter("description"));
        userFeedBackEntity.setStatus(Integer.valueOf(request.getParameter("status")));
        userFeedBackEntity.setCreateId(request.getParameter("createId"));
        userFeedBackEntity.setUpdateId(request.getParameter("updateId"));
        MultipartFile clientFile0 = multipartRequest.getFile("uploadFile0");
        List uploadFiles = new ArrayList<>();
        uploadFiles.add(clientFile0);
        sysUserFeedBackService.insertUserFeedBackRecord(userFeedBackEntity, uploadFiles);
        return result.success(1);
    } catch (IOException e) {
        e.printStackTrace();
        return result.error("Failed to save user feedback");
    }
}

@Override
public int insertUserFeedBackRecord(SysUserFeedBackEntity record, List uploadFiles) throws IOException {
    logger.info(" insert  record into the table");
    sysUserFeedBackMapper.insertUserFeedBack(record);
    for (MultipartFile uploadFile : uploadFiles) {
        MultipartFile aa = uploadFile;
        if (!aa.getOriginalFilename().equals("null")){ // 这边前端进行压缩的时候有判断，如果没有上传文件，就把名字置为null 所以这边判断如果不上null 才会上传
            int fb_id = sysUserFeedBackMapper.getFBId(record.getSubject(), record.getCreateId());
            logger.info(" get the fb_id {} after insert ", fb_id);
            record.setFbId(fb_id);
            logger.info(" insert attachments records into the attachments table");
            if (uploadFile != null) {
                record.setFbFileName(aa.getOriginalFilename());
                insertRecordIntodocument(record, uploadFile.getBytes());//上传字节流 并把对应的路径等信息保存到table
            }
        }else{
            logger.info("not upload file");
        }

    }
    return 1;
}

@GetMapping("/downloadFiles")
public void downloadFiles(@RequestParam int fbId, HttpServletResponse response) throws IOException {
    HashMap fileInfos = sysUserFeedBackService.downloadFiles(fbId);// 下载对应的字节流文件
    for (String key : fileInfos.keySet()) {
        // reset response
        response.reset();
        response.setHeader("Content-Disposition", "attachment; filename=" + key);
        response.setContentType("application/octet-stream; charset=utf-8") ;
        response.setCharacterEncoding("UTF-8");
        OutputStream outputStream = new BufferedOutputStream(response.getOutputStream());
        byte[] bytes = fileInfos.get(key);
        outputStream.write(bytes);
        outputStream.close();

    }
}

对应前端代码：

    downloadFile(row) {

      window.location.href =

              "/midmetric/userFeedBack/downloadFiles?fbId=" + row.fbId;

    },