code: public HttpResponse doHttpCall(final String urlString,
  			final File fileToBeSent, final String proxyHost,
  			final int proxyPort, final String fileEncoding) throws IOException {
  		return this.doHttpCall(urlString,
  				fileUtil.getFileContentsAsString(fileToBeSent, fileEncoding),
  				"", "", proxyHost, 0, Collections.<String, String> emptyMap());
  	}
docs: Sends a string to a URL. This is very helpful when SOAP web services are
  involved or you just want to post a XML message to a URL. If the
  connection is done through a proxy server you can pass the proxy port and
  host as parameters.
  
  @param urlString
  the URL to post to
  @param fileToBeSent
  the file to be sent
  @param proxyHost
  any proxy host that needs to be configured
  @param proxyPort
  any proxy port that needs to be configured
  @param fileEncoding
  the file encoding. Examples: "UTF-8", "UTF-16".
  @return a {@link HttpResponse} object containing the response code and
  the response string
  @throws IOException
  if a I/O error occurs