final public function getFromMap($fieldName, $key, $default = null)
    {
        if (!$this->isInMap($fieldName, $key)) {
            return $default;
        }
        return $this->data[$fieldName][$key];
    }
final public function getFromMap($fieldName, $key, $default = null)
    {
        if (!$this->isInMap($fieldName, $key)) {
            return $default;
        }
        return $this->data[$fieldName][$key];
    }
{@inheritdoc}