How to persist a Hibernate child entity without loading the parent-side Set collection

Question

We are using Hibernate 3.5.6-Final with Hazelcast 3.6.1 2nd level cache.

Situation

I have a bi-directional, one-to-many relation between a Parent

Answer 1

I found a solution to my problem. I solved it by adding a new method addChild to the Parent that looks as follows:

 public void addChild(Child child) {
     child.setParent(this);
     if (Hibernate.isInitialized(getChildren()) {
         getChildren().add(child);
     } else {
         Hibernate.getSessionFactory().getCache().evictCollection(
             getClass().getName()+".children", this.getId());
     }
 }

Thus: if the children have already been loaded for some reason, the new child is added to the children set. This ensures that an already loaded set stays consistent. If the set is not loaded yet, I just set the parent to the child and evict the 2nd level cache (that this is needed is described here: https://github.com/hibernate/hibernate-orm/pull/580). As the set is not loaded yet it can also not be inconsistent. When the set is accessed afterwards, Hibernate will load the set including the new child.