Steve Ebersole, it's not obvious (at least to me) that the following could cause concurrent access to Session/EntityManager.:

em.createQuery("from MyEntity").getResultList().parallelStream()
            .forEach((e) -> {
                        // do something that causes lazy entities to get initialized
                        e.getReferencedEntity();
                        e.getAnotherReferencedEntity(); 
             });

It happens here because the entities are lazy and get initialized.

Collection#parallelStream Javadoc says:

"Returns a possibly parallel Stream with this collection as its source. It is allowable for this method to return a sequential stream."

I think it would be worth at least documenting that calling List#parallelStream on the List returned by Query#getResultList can cause problems if it contains lazy entities, associations, or properties.