code: public static Response post(URI uri, String body, ContentType contentType,
                                  String username, String password) throws URISyntaxException, HttpException {
          return postBody(new HttpPost(uri), body, contentType, new UsernamePasswordCredentials(username, password), null);
      }
docs: Performs an HTTP POST on the given URL.
  Basic auth is used if both username and password are not null
  
  @param uri         The URI to connect to.
  @param body        The POST body.
  @param contentType The ContentType of the POST body.
  @param username    Credentials - username
  @param password    Credentials - password
  @return The HTTP response as Response object.
  @throws URISyntaxException
  @throws HttpException