public function writeShufflingGroup(ShufflingGroup $shufflingGroup)
    {
        try {
            $identifiers = $shufflingGroup->getIdentifiers();
            $this->writeTinyInt(count($identifiers));
            foreach ($identifiers as $identifier) {
                $this->writeString($identifier);
            }
            
            $fixedIdentifiers = $shufflingGroup->getFixedIdentifiers();
            $this->writeTinyInt(count($fixedIdentifiers));
            foreach ($fixedIdentifiers as $identifier) {
                $this->writeString($identifier);
            }
        } catch (BinaryStreamAccessException $e) {
            $msg = "An error occured while writing a shufflingGroup.";
            throw new QtiBinaryStreamAccessException($msg, $this, QtiBinaryStreamAccessException::SHUFFLING_GROUP, $e);
        }
    }