protected function createAction($handler)
{
if ($handler instanceof Closure) {
$action = $handler;
} else {
if (($pos = strpos($handler, '@')) !== false) {
$class = substr($handler, 0, $pos);
$method = substr($handler, $pos + 1);
if ($class[0] !== '\\' && $this->controllerNamespace) {
$class = $this->controllerNamespace . '\\' . $class;
}
$action = [$this->get($class), $method];
} else {
throw new HttpException(404);
}
}
return $action;
}