Hibernate and H2 “Referential integrity constraint violation” for OneToMany bidirectional mapping

Question

So I have two simple beans -- FatKid and Hamburgers. Now, for reasons unbeknownst to me I need to be able to not only look up all of the hamburgers someone ate, but also who at

Answer 1

Your mappings look weird to me. You have a @JoinColumn in both sides of the relationship, each pointing to the primary key of the other table. That doesn't seem to be a OneToMany relationship.

Your OneToMany should tell the owner of the relationship:

@OneToMany(cascade = CascadeType.ALL, mappedBy = "whoDoneAteMe")
public List<Hamburger> getHamburgers() {
    return hamburgers;
}

and then in the other side:

@ManyToOne(cascade = CascadeType.ALL)
@JoinColumn(name = "fatkid_id")
public FatKid getWhoDoneAteMe() {
    return whoDoneAteMe;
}

You might be able to optimize your code further too. As your FatKid objects are aware of the Hamburger objects and you have configured cascading, you could do:

    session.beginTransaction();
    FatKid fk = new FatKid();
    fk.setName("Darrell");

    Hamburger hamburger_1 = new Hamburger();
    hamburger_1.setDescription("Juicy quarter pounder with cheese");
    hamburger_1.setWhoDoneAteMe(fk);
    fk.getHamburgers().add(hamburger1);

    Hamburger hamburger_2 = new Hamburger();
    hamburger_2.setDescription("Ground buffalo burger topped with bacon and a sunny-side egg");
    hamburger_2.setWhoDoneAteMe(fk);
    fk.getHamburgers().add(hamburger2);

    session.save(fk);
    session.getTransaction().commit();

    sessionFactory.close();

The above code should save the complete object graph with just one commit operation and in a single transaction.