return backingMap.getEntry(entryIndex);
      }
    };
  }

  /** Allocation-free implementation of {@code target.addAll(this)}. */
  void addTo(Multiset<? super E> target) {
    checkNotNull(target);
    for (int i = backingMap.firstIndex(); i >= 0; i = backingMap.nextIndex(i)) {
      target.add(backingMap.getKey(i), backingMap.getValue(i));
    }
  }

  @Override
  final int distinctElements() {

  ConcurrentMap<String, AtomicInteger> backingMap;
  ConcurrentHashMultiset<String> multiset;

  @SuppressWarnings("unchecked")
  @Override
  protected void setUp() {
    backingMap = mock(ConcurrentMap.class);
    when(backingMap.isEmpty()).thenReturn(true);

    multiset = ConcurrentHashMultiset.create(backingMap);
  }

  public void testCount_elementPresent() {

    private final NavigableMap<K, V> backingMap;

    StandardImplForwardingNavigableMap(NavigableMap<K, V> backingMap) {
      this.backingMap = backingMap;
    }

    @Override
    protected NavigableMap<K, V> delegate() {
      return backingMap;
    }

    @Override
    public boolean containsKey(Object key) {
      return standardContainsKey(key);

   *     call, or switch to a {@code HashMap<K, ArrayList<V>>}.
   */
  @Deprecated
  public void trimToSize() {
    for (Collection<V> collection : backingMap().values()) {
      ArrayList<V> arrayList = (ArrayList<V>) collection;
      arrayList.trimToSize();
    }
  }

  /**