code: @Override
      public void writeTo(OutputStream output) throws IOException {
          try {
              if (!firstAttempt && isRepeatable()) content.reset();
  
              firstAttempt = false;
              inputStreamRequestEntity.writeTo(output);
          } catch (IOException ioe) {
              if (originalException == null) originalException = ioe;
              throw originalException;
          }
      }
docs: Resets the underlying InputStream if this isn't the first attempt to
  write out the request, otherwise simply delegates to
  InputStreamRequestEntity to write out the data.
  <p>
  If an error is encountered the first time we try to write the request
  entity, we remember the original exception, and report that as the root
  cause if we continue to encounter errors, rather than masking the
  original error.
  
  @see org.apache.commons.httpclient.methods.RequestEntity#writeRequest(java.io.OutputStream)