| Create two Entities: Book and Article Book contains SortedSet of Articles, sorted by number of pages Use @SortNatural and let Article implement Comparable EagerLoading=true Article has association to Book EagerLoading=true Try to fetch via JPQL all articles, see Testcases attached Testcase "getArticleWithJoinFetch" is valid "SELECT DISTINCT a FROM Article a LEFT JOIN FETCH a.book" LInk to Book is PREFETCHED with JOIN FETCH Testcase "getArticleWithEagerLoadingWithoutJoinFetch" fails "SELECT DISTINCT a FROM Article a" Eager-Loading fetchtes Book, then tries to fetch Articels NPE is thrown while compareTo (from Comparable) is trying to sort the articles. Articles are not initialized when getting compared Could be a problem with the PersistentSortedSet Implementation |