public function getRandom()
    {
        $this->internalDataListUpdate();
        $count = sizeof($this->internalDataListData);
        if ($count > 0) {
            $index = rand(0, $count - 1);
            if (isset($this->internalDataListData[$index])) {
                return $this->internalDataListUpdateValueIfNeeded($this->internalDataListData, $index);
            }
        }
        return null;
    }