title: File Upload Progress Bar with Spring?
body: <p>I have the following RestController for uploading files into my server side.</p>
  
  <pre><code>    @RequestMapping(value="/upload", method=RequestMethod.POST )
      @CrossOrigin
      public SimpleHttpResponse uploadFile(@RequestParam("uploadItem") MultipartFile fileUpload )
      {
          System.out.println(fileUpload.getOriginalFilename());
          try {
              byte[] fileBytes = fileUpload.getBytes();
              Files.write(Paths.get("C:\\Users\\" + fileUpload.getOriginalFilename()), fileBytes);
          } catch (IOException e) {
              // TODO Auto-generated catch block
              e.printStackTrace();
  
          }
  
          return new SimpleHttpResponse(true);
      }
  </code></pre>
  
  <p>Is there anyway to track the bytes received at any given moment and expose it to the UI ? Lot of the examples I see on Google are using Servlets/JSPs with Apache Commons. Is there a Spring based solution to get the progress or way to  integrate Apache Commons File Upload with Spring ? Ideally, there would be a way to identify multiple file uploads from different users(or even from same user). Thanks for any pointers.  </p>