/**
  * Return the rule corresponding route parameter.
  * @param string $ruleParameter
  * @param Route $route
  * @return mixed
  */
 private function getRuleCorrespondingRouteParameter($ruleParameter, Route $route)
 {
     if (isset($this->pathParameters[$ruleParameter]) && !empty($this->pathParameters[$ruleParameter])) {
         return $this->pathParameters[$ruleParameter];
     }
     return $route->getDefaultValue($ruleParameter);
 }