OneToOne bidirectional

em.getTransaction().begin();
Owner owner = new Owner("bla", 42);
int id = owner.getId();
Foo foo = new Foo(true); // you probably just could pass owner here
owner.setFoo(foo);
em.persist(owner);
em.flush();
// owner = em.find(Owner.class, id); // try with and without this line
System.out.println(owner.getFoo().getSomeValue());
System.out.println(owner.getFoo().getOwner().getSomeOtherValue());
em.getTransaction().commit();