private function findContactsByIds($ids)
    {
        if (0 === count($ids)) {
            return [];
        }

        $queryBuilder = $this->entityManager->createQueryBuilder()
            ->select('CONCAT(\'c\', c.id) AS id, CONCAT(CONCAT(c.firstName, \' \'), c.lastName) AS name')
            ->from($this->contactEntityClass, 'c')
            ->where('c.id IN (:ids)');

        $query = $queryBuilder->getQuery();
        $query->setParameter('ids', $ids);

        return $query->getArrayResult();
    }