code: public static String postFrom(
                      final URL to_url,
                      final Reader from_reader,
                      final MediaType media_type
                      )
      {
          ReaderRequestCallback  callback =
                          new ReaderRequestCallback( from_reader, media_type );
          String  location = _execute( to_url, HttpMethod.POST, callback,
                          new LocationHeaderResponseExtractor() );
  
          return location;
      }
docs: HTTP POST: Reads the contents from the specified reader and sends them to the URL.
  
  @return
  the location, as an URI,  where the resource is created.
  @throws  HttpException
  when an exceptional condition occurred during the HTTP method execution.