code: private boolean isDownloadParallel(PresignedUrlDownloadRequest request, Long startByte, Long endByte,
                                         long partialObjectMaxSize) {
          return !configuration.isDisableParallelDownloads() && !(s3 instanceof AmazonS3Encryption)
                 // Can't rely on set range as endbyte can be set to random number longer than actual size. This results in
                 // making large number of partial requests even after the entire file is read from S3
                 && request.getRange() == null
                 // This is when SDK can compute the endByte through the object metadata
                 && (startByte != null && endByte != null && endByte - startByte + 1 > partialObjectMaxSize);
      }
docs: Returns a boolean value indicating if object can be downloaded in parallel
  when using presigned url.