public function setMinStockLevel($minStockLevel)
{
$minStockLevel = intval($minStockLevel);
if ($minStockLevel < 0) {
throw new MinStockLevelOutOfRangeException();
}
$this->minStockLevel = $minStockLevel;
if ($this->getStockLevel() < $this->getMinStockLevel()) {
$this->setLowStock(true);
} else {
$this->setLowStock(false);
}
}