protected function validateRouteMapping(Route\Mapping $mapping)
    {
        if (!class_exists($mapping->controller())) {
            throw new Exception("Controller '{$mapping->controller()}' not found");
        }

        if (!method_exists($mapping->controller(), $mapping->action())) {
            throw new Exception("Action '{$mapping->action()}' does not exist in controller '{$mapping->controller()}'");
        }
    }