Multiple @ManyToOne fields pointing to same entity in JPA / Hibernate

Question

I have an Order entity that has a billingAddress and a shippingAddress. I also have an Address entity. I am trying to mak

Answer 1

Regarding your first question: is it a ManyToOne?

It depends. If several orders can have the same shipping address, then it's a ManyToOne. If only one order can have a given shipping address, then it's a OneToOne. Same for billing address.

I'm not sure making the association bidirectional is a good idea. I probably wouldn't do it in this case. But if you want to make it bidirectional, then you have to make them bidirectional. You indeed have two different associations here. The mapping would thus look like the following:

@OneToMany(mappedBy = "shippingAddress")
private Set<Order> shippedOrders;

@OneToMany(mappedBy = "billingAddress")
private Set<Order> billedOrders;

or, if the association is in fact a OneToOne (see answer to the first question):

@OneToOne(mappedBy = "shippingAddress")
private Order shippedOrder;

@OneToOne(mappedBy = "billingAddress")
private Order billedOrder;