private function getSortedAndEncodedParams(OAuthRequest $request)
 {
     $params = array();
     MapUtils::decodeAndAppendEntries($request->getQueryStringParams(), $params);
     MapUtils::decodeAndAppendEntries($request->getBodyParams(), $params);
     MapUtils::decodeAndAppendEntries($request->getOauthParameters(), $params);
     $params = MapUtils::sort($params);
     return URLUtils::percentEncode(MapUtils::concatSortedPercentEncodedParams($params));
 }