code: public static HttpEntity get(HttpClient httpClient,
                                   URI requestURI,
                                   OutputStream sink) throws IOException {
          HttpEntity entity = doGet(httpClient, requestURI);
          if (entity != null) {
              entity.writeTo(sink);
          }
          return entity;
      }
docs: Performs an HTTP GET using the given client, sending the response body
  to the given stream (which won't be auto-closed).
  
  @param httpClient the client to use.
  @param requestURI the http or https url.
  @param sink the stream to send the content to (it won't be auto-closed)
  @return the resulting entity
  @throws IOException if the request fails for any reason, including
  a non-200 status code.