public function getCheckerFromFQCN($checkerName)
    {
        $checkerName = trim($checkerName, '\\');
        if (!class_exists($checkerName)) {
            throw new \RuntimeException('Checker FQCN does not exists');
        }

        foreach ($this->checkers as $checker) {
            if ($checker instanceof $checkerName) {
                return $checker;
            }
        }

        throw new RuntimeException('Checker could not be found');
    }