code: @Beta
    void serverErrorCallback() throws IOException {
      Preconditions.checkNotNull(currentRequest, "The current request should not be null");
  
      // Query the current status of the upload by issuing an empty PUT request on the upload URI.
      currentRequest.setContent(new EmptyContent());
      currentRequest.getHeaders().setContentRange("bytes */" + mediaContentLengthStr);
    }
docs: {@link Beta} <br/>
  The call back method that will be invoked on a server error or an I/O exception during
  resumable upload inside {@link #upload}.
  
  <p>
  This method changes the current request to query the current status of the upload to find how
  many bytes were successfully uploaded before the server error occurred.
  </p>