protected function getMax()
	{
		if ( ! $this->locked) {
			//\Log::info('Should lock before changes');
		}

		$dql = "SELECT MAX(e.right) FROM {$this->className} e";
		$dql .= $this->getAdditionalCondition('WHERE');
		$query = $this->entityManager
				->createQuery($dql);
		$max = (int) $query->getSingleScalarResult();

		// Maybe array helper stores even bigger value.
		// In reality it won't happen because items are flushed on DQL run.
		$maxArrayHelper = $this->arrayHelper->getCurrentMax();
		$max = max($max, $maxArrayHelper);

		return $max;
	}