static final FieldSetter<? super ConcurrentHashMultiset<?>> COUNT_MAP_FIELD_SETTER =
        Serialization.getFieldSetter(ConcurrentHashMultiset.class, "countMap");
  }

  /**
   * Creates a new, empty {@code ConcurrentHashMultiset} using the default initial capacity, load
   * factor, and concurrency settings.
   */
  public static <E> ConcurrentHashMultiset<E> create() {

  }

  private void testAddAndRemove(ConcurrentMap<String, AtomicInteger> map)
      throws ExecutionException, InterruptedException {

    final ConcurrentHashMultiset<String> multiset = new ConcurrentHashMultiset<>(map);
    int nThreads = 20;
    int tasksPerThread = 10;
    int nTasks = nThreads * tasksPerThread;
    ExecutorService pool = Executors.newFixedThreadPool(nThreads);

      }
    },
    ConcurrentHashMultisetImpl {
      @Override
      public <E extends Comparable<E>> Multiset<E> create(Collection<E> contents) {
        return ConcurrentHashMultiset.create(contents);
      }
    },
    ImmutableMultisetImpl {
      @Override
      public <E extends Comparable<E>> Multiset<E> create(Collection<E> contents) {

      }
    },
    ConcurrentHashMultisetImpl {
      @Override
      public <E extends Comparable<E>> Multiset<E> create(Collection<E> contents) {
        return ConcurrentHashMultiset.create(contents);
      }
    },
    ImmutableMultisetImpl {
      @Override
      public <E extends Comparable<E>> Multiset<E> create(Collection<E> contents) {