How to adapt documentation example code for the soft deleted entities?

Support
#1

Handling Changes Before Commit has next code that throw IllegalStateException: No results on Order deleting.

@Component
public class OrderLineEventListener {

    @Autowired
    private DataManager dataManager;

    @EventListener
    void onOrderLineChangedBeforeCommit(EntityChangedEvent<OrderLine> event) {
        Order order;
        if (event.getType() == EntityChangedEvent.Type.DELETED) {
            Id<Order> orderId = event.getChanges().getOldReferenceId("order");
            order = dataManager.load(orderId).one();
        } else {
            OrderLine orderLine = dataManager.load(event.getEntityId()).one();
            order = orderLine.getOrder();
        }
        BigDecimal amount = order.getLines().stream()
                .map(line -> line.getProduct().getPrice().multiply(
                        BigDecimal.valueOf(line.getQuantity()))
                )
                .reduce(BigDecimal.ZERO, BigDecimal::add);
        order.setAmount(amount);
        dataManager.save(order);
    }
}

Handling of References

public class Order {
    // ...
    @OnDelete(DeletePolicy.CASCADE)
    @Composition
    @OneToMany(mappedBy = "order")
    private List<OrderLine> lines;
#2

Perhaps if the related Order is already deleted, you don’t want to change its amount. So I would just exit the listener in this case:

@EventListener
public void onOrderLineChangedBeforeCommit(EntityChangedEvent<OrderLine> event) {
    Order order;
    if (event.getType() == EntityChangedEvent.Type.DELETED) {
        Id<Order> orderId = event.getChanges().getOldReferenceId("order");
        order = dataManager.load(orderId).optional().orElse(null);
        if (order == null)
            return; // the order has just been soft-deleted
    } else {