About file upload and download

If it's just a simple file upload and download, it's still relatively simple . The code is as follows ：

Upload files ：

    @PostMapping("/uploadFile")
    @ApiOperation(" Upload report file ")
    public ResponseResult uploadAudio(@RequestParam(value = "file") MultipartFile file) {

        if (file.isEmpty()) {
            return ResponseResult.failed(" The file cannot be empty ");
        }

        // File address does not exist , Create 
        File dir = new File(path);
        if (!dir.exists()) {
            dir.mkdirs();
        }

        // file extension 
        String prefix = file.getOriginalFilename().substring(file.getOriginalFilename().lastIndexOf("."));

        //if (".mp3".equals(prefix) || ".m4a".equals(prefix) || ".wav".equals(prefix)) {

       // String fileName = UUID.randomUUID().toString().replaceAll("-", "") + prefix;

        String fileName = file.getOriginalFilename();

        File newFile = new File(path + fileName);
        log.info(" Upload path :" + path);
        log.info(" file name :" + fileName);
        try {
            file.transferTo(newFile);
//               request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+
            String url = dbPath + fileName;
            Map<String,Object> map=new HashMap<>();
            map.put("url",url);
            map.put("name",fileName);
            return ResponseResult.ok(map, " Upload successful ");
        } catch (IOException e) {
            e.printStackTrace();
            return ResponseResult.failed(" Upload failed ");
        }
        //  }
        // return ResponseResult.failed(" The file format does not meet the requirements ");

    }

File download ：

@GetMapping("/exportFile")
    @ApiOperation(" Download the file ")
    public void exportQualityReport(@RequestParam("id") Integer id,HttpServletResponse response)throws IOException{
        InputStream inputStream = null;
        ServletOutputStream outputStream = null;
        if (id!=null){
            QualityReportVo vo=reportService.getById(id);
            if (vo!=null){
                try {
                    String fileName = vo.getFileName();
                    String path1 =locationPre+vo.getReportLocation();
                    Resource resource = new DefaultResourceLoader().getResource("file:" + path1);
                    FileConvertUtil.responseInit(response, fileName);
                    inputStream = resource.getInputStream();
                    outputStream = response.getOutputStream();
                    IOUtils.copy(inputStream, outputStream);
                    response.flushBuffer();
                } catch (Exception e) {
                    e.printStackTrace();
                    throw new IOException(" Download error ");
                } finally {
                    try {
                        if (outputStream != null) {
                            outputStream.close();
                        }
                        if (inputStream != null) {
                            inputStream.close();
                        }
                    } catch (Exception e) {
                        throw new CustomException(" Download error ");
                    }
                }
            }else {
                throw new IOException(" file id non-existent ");
            }
        }else {
            throw new CustomException("id Can't be empty ");
        }

    }

I forgot to make up an important point , Is to set the download rules , That is, coding , What kind of image to download

/**
 *  Set file download rules 
 *
 * @param response
 * @param fileName
 */
public static void responseInit(HttpServletResponse response, String fileName) {
    response.reset();

    response.setHeader("Content-Disposition", "attachment;filename=" + new
            String(fileName.getBytes(StandardCharsets.UTF_8), StandardCharsets.ISO_8859_1));

    response.setContentType("application/octet-stream; charset=utf-8");

    response.setCharacterEncoding("UTF-8");

}

Just use your own path to upload files , The path in the code is because it is stored , Show only relative paths , So when taking a path , It needs to be prefixed for processing . Then I configured the path on the configuration file .