code: public Observable<Void> getLongRunningOperationStatusAsync(String operationStatusLink) {
          return getLongRunningOperationStatusWithServiceResponseAsync(operationStatusLink).map(new Func1<ServiceResponse<Void>, Void>() {
              @Override
              public Void call(ServiceResponse<Void> response) {
                  return response.body();
              }
          });
      }
docs: The Get Operation Status operation returns the status of the specified operation. After calling an asynchronous operation, you can call Get Operation Status to determine whether the operation has succeeded, failed, or is still in progress.
  
  @param operationStatusLink Location value returned by the Begin operation.
  @throws IllegalArgumentException thrown if parameters fail the validation
  @return the {@link ServiceResponse} object if successful.