code: public PrePersist<MappedSuperclass<T>> getOrCreatePrePersist()
     {
        Node node = childNode.getOrCreate("pre-persist");
        PrePersist<MappedSuperclass<T>> prePersist = new PrePersistImpl<MappedSuperclass<T>>(this, "pre-persist", childNode, node);
        return prePersist;
     }
docs: If not already created, a new <code>pre-persist</code> element with the given value will be created.
  Otherwise, the existing <code>pre-persist</code> element will be returned.
  @return  a new or existing instance of <code>PrePersist<MappedSuperclass<T>></code>