private static void saveOrUpdateInvoice(Invoice invoice) {
updateOrStoreObject(invoice);
Customer customer = invoice.getCustomer();
for (Address address : customer.getAddresses()) {
updateOrStoreObject(address);
}
updateOrStoreObject(customer);
ProductGroup group = invoice.getProductGroup();
group.setInvoice(invoice);
updateOrStoreObject(group);
for (ProductLine line : group.getProductLines()) {
line.setProductPrice(line.getProduct().getPrice());
line.setProductGroup(invoice.getProductGroup());
updateOrStoreObject(line);
}
}