public function register($postType, $className)
    {
        if (!is_subclass_of($className, 'Tev\Post\Model\AbstractPost')) {
            throw new Exception("Given class '$className' is not instance of 'Tev\Post\Model\AbstractPost'");
        }

        $this->registeredMappings[$postType] = $className;

        return $this;
    }