code: public static HttpURLConnection copyFrom(final URI uri, final FileRequestOptions fileOptions,
              final OperationContext opContext, final AccessCondition sourceAccessCondition,
              final AccessCondition destinationAccessCondition, String source)
              throws StorageException, IOException, URISyntaxException {
  
          final HttpURLConnection request = BaseRequest.createURLConnection(uri, fileOptions, null, opContext);
  
          request.setFixedLengthStreamingMode(0);
          request.setDoOutput(true);
          request.setRequestMethod(Constants.HTTP_PUT);
  
          request.setRequestProperty(Constants.HeaderConstants.COPY_SOURCE_HEADER, source);
  
          if (sourceAccessCondition != null) {
              sourceAccessCondition.applyConditionToRequest(request);
          }
  
          if (destinationAccessCondition != null) {
              destinationAccessCondition.applyConditionToRequest(request);
          }
  
          return request;
      }
docs: Creates a request to copy a file, Sign with 0 length.
  
  @param uri
  A <code>java.net.URI</code> object that specifies the absolute URI.
  @param fileOptions
  A {@link FileRequestOptions} object that specifies execution options such as retry policy and timeout
  settings for the operation. Specify <code>null</code> to use the request options specified on the
  {@link CloudFileClient}.
  @param opContext
  An {@link OperationContext} object that represents the context for the current operation. This object
  is used to track requests to the storage service, and to provide additional runtime information about
  the operation.
  @param source
  The canonical path to the source file,
  in the form /<account-name>/<share-name>/<directory-path>/<file-name>.
  @param sourceAccessConditionType
  A type of condition to check on the source file.
  @param sourceAccessConditionValue
  The value of the condition to check on the source file
  @return a HttpURLConnection configured for the operation.
  @throws StorageException
  an exception representing any error which occurred during the operation.
  @throws IllegalArgumentException
  @throws IOException
  @throws URISyntaxException