@Before public void setUp() { List<Rating> ratings = ImmutableList.of(Rating.create(42, 1, 3.2), Rating.create(39, 1, 2.4), Rating.create(42, 2, 2.5)); StaticDataSource source = StaticDataSource.fromList(ratings); dao = source.get(); statistics = InteractionStatistics.create(dao); recommender = new PopularityRankItemScorer(statistics); }