### Question:
ReviewDAO { public List<Review> unseen() { List<Review> unseen = new ArrayList<Review>(); for (Review r : reviews) { if (!r.isMarkedAsRead()) { unseen.add(r); } } return unseen; } ReviewDAO(); boolean add(Review newReview); void addAll(List<Review> reviews); List<Review> all(); List<Review> unseen();  }### Answer:
@Test public void callingUnseenForNewlyConstructedDaoDoesNotReturnNull() { assertNotNull(dao.unseen()); }