class SessionRouteRegistry extends AbstractRouteRegistry {

    @Override
    public Optional<Class<? extends Component>> getNavigationTarget(
            String url) {
        Objects.requireNonNull(url, "pathString must not be null.");
        final Optional<Class<? extends Component>> target = getConfiguration()
                .getTarget(url);
        if (target.isPresent()) {
            return target;
        }

        return getParentRegistry().getNavigationTarget(url);
    }

      SessionRouteRegistry(VaadinSession session);

}