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I have two entities User and Role which holds a bidirectional relationship.
Basically I want to create as many roles as I want, without the need to add any user to it, but every time a new user entity has to become persistent it must belong at least to a role.
private List<User> users = new ArrayList<User>();
I can create new role and users, but the problem is on the USR_ROLE_FK table which is empty, so not consistent relationship between entities.
On the client side, before to pass the new user entity to persist, I first retrieve the detached role entity, then add it to the new user and finally passed to the ejb.
Personally I think I am missing something about the cascading property, but after several attempts and fails I am stuck.
I need your help, at least some resources with practical examples.
Thanks in advance
- You have put mappedBy on User side, that means the role side is the owning side. I think it's better to make the User side as the owning side. Because the roles are attached or detached to users and not the other way round.