### Question:
JDKImperativeDeckOfCardsAsSortedSet { public Map<Suit, Long> countsBySuit() { Map<Suit, Long> result = new HashMap<>(); for (Card card : this.cards) { Suit suit = card.suit(); Long value = result.get(suit); if (value == null) { value = Long.valueOf(0); } result.put(suit, value + 1); } return result; } JDKImperativeDeckOfCardsAsSortedSet(); Deque<Card> shuffle(Random random); Set<Card> deal(Deque<Card> deque, int count); List<Set<Card>> shuffleAndDeal(Random random, int hands, int cardsPerHand); List<Set<Card>> dealHands(Deque<Card> shuffled, int hands, int cardsPerHand); SortedSet<Card> diamonds(); SortedSet<Card> hearts(); SortedSet<Card> spades(); SortedSet<Card> clubs(); Map<Suit, Long> countsBySuit(); Map<Rank, Long> countsByRank(); SortedSet<Card> getCards(); Map<Suit, SortedSet<Card>> getCardsBySuit();  }### Answer:
@Test public void countsBySuit() { Assert.assertEquals(Long.valueOf(13), this.jdkDeck.countsBySuit().get(Suit.CLUBS)); }