private function mapRoute2Index($route)
    {
        $routeIndex = $this->mapRoute2IndexKey($route);

        if ($routeIndex) {
            return [$routeIndex, $this->index[$routeIndex]];
        }

        $msg = t("The route '!ROUTE' does not exists in the index.", [
            "!ROUTE" => $route
        ]);
        throw new \Anax\Exception\NotFoundException($msg);
    }