@Test
@Transactional
public void testCopy() {
EntityManager em = bookDao.getEntityManager();
CriteriaBuilder cb = em.getCriteriaBuilder();
CriteriaQuery<Book> criteria = cb.createQuery(Book.class);
// Fetch join
Root<Book> root = criteria.from(Book.class);
Path<String> path = root.join("author").<String>get("name");
root.fetch("author");
criteria.select(root);
// SubQuery
Subquery<String> sq = criteria.subquery(String.class);
Root<Author> author = sq.from(Author.class);
sq.select(author.<String>get("name"));
sq.where(cb.equal(author.<String>get("name"), "Rod"));
criteria.where(cb.in(path).value(sq));
CriteriaQuery<Book> copy = cb.createQuery(Book.class);
JpaUtils.copyCriteria(criteria, copy);
List<Book> copyBooks = em.createQuery(copy).getResultList();
List<Book> books = em.createQuery(criteria).getResultList();
assertEquals(books, copyBooks);
}
@Test
@Transactional
public void testCountCriteria() {
EntityManager em = bookDao.getEntityManager();
CriteriaBuilder cb = em.getCriteriaBuilder();
CriteriaQuery<Book> criteria = cb.createQuery(Book.class);
Root<Book> root = criteria.from(Book.class);
Join<Book, Author> join = root.join("author");
criteria.where(join.isNotNull());
CriteriaQuery<Long> countCriteria = JpaUtils.countCriteria(em, criteria);
Long result = em.createQuery(countCriteria).getSingleResult();
log.debug("Count: " + result);
}
