public function unserialize($data)
{
$data = unserialize($data);
$this->productId = $data['productId'];
$this->position = $data['position'];
$this->unitPrice = $data['unitPrice'];
$this->price = $data['price'];
$this->priceIncludingVat = $data['priceIncludingVat'];
$this->vatRate = $data['vatRate'];
$this->quantity = $data['quantity'];
$this->options = $data['options'];
$this->name = $data['name'];
$this->productCode = $data['productCode'];
}