HibernateException: A collection with cascade="all-delete-orphan" was no longer referenced by the owning entity instance: com.myapp.domainentitiesEJB3.member.Member.users

here's how i write my set methods in my EJB3 java entity objects when a collection is to be set and hibernate is used for persistence:

    public void setUsers(List<RbacUser> users_) {
        if (users == null) users = new ArrayList<RbacUser>();
        users.clear();
        if(users_ != null && !users_.isEmpty()) users.addAll(users_);
    }

if you try to write it like this:
    public void setUsers(List<RbacUser> users_) {
        users = users_;
    }

hibernate may give you an error like this:
HibernateException: A collection with cascade="all-delete-orphan" was no longer referenced by the owning entity instance: com.myapp.domainentitiesEJB3.member.Member.users