/**
* @inheritdoc
*/
public function addChild(CustomerInterface $child)
{
if (!$this->hasChild($child)) {
$this->children->add($child);
}
return $this;
}
/**
* @inheritdoc
*/
public function addCustomer(CustomerInterface $customer)
{
if (!$this->hasCustomer($customer)) {
$this->customers->add($customer);
}
return $this;
}