public function setFlats_count($flats_count = null)
{
// validation for constraint: int
if (!is_null($flats_count) && !is_numeric($flats_count)) {
throw new \InvalidArgumentException(sprintf('Invalid value, please provide a numeric value, "%s" given', gettype($flats_count)), __LINE__);
}
$this->flats_count = $flats_count;
return $this;
}