private static <E extends @Nullable Object> Entry<E> entry(final E element, final int count) {
    return Multisets.immutableEntry(element, count);
  }

  private static <E extends @Nullable Object> Entry<E> control(E element, int count) {
    return HashMultiset.create(Collections.nCopies(count, element)).entrySet().iterator().next();
  }

  public void testToString() {

    private final AtomicInteger count = new AtomicInteger();
    private volatile RemovalNotification<K, V> lastNotification;

    @Override
    public void onRemoval(RemovalNotification<K, V> notification) {
      count.incrementAndGet();
      lastNotification = notification;
    }

    public int getCount() {
      return count.get();
    }

    public K getLastEvictedKey() {

    }
  }

  @Param EncodingOption encoding;

  @Param({"10", "100", "10000"})
  int n;

  private final byte[][] encodingInputs = new byte[INPUTS_COUNT][];
  private final String[] decodingInputs = new String[INPUTS_COUNT];

  @BeforeExperiment
  public void setUp() {
    Random rng = new Random();
    for (int i = 0; i < encodingInputs.length; i++) {
      encodingInputs[i] = new byte[n];

   * support concurrent multisets whose content may change while the method is running.
   *
   * <p>The serialized output consists of the number of distinct elements, the first element, its
   * count, the second element, its count, and so on.
   */
  static <E extends @Nullable Object> void writeMultiset(
      Multiset<E> multiset, ObjectOutputStream stream) throws IOException {
    int entryCount = multiset.entrySet().size();

    multiset.add("bar");
    assertEquals(3, multiset.size());
    assertEquals(2, multiset.count("foo"));
  }

  public void testCreateWithSize() {
    Multiset<String> multiset = HashMultiset.create(50);
    multiset.add("foo", 2);
    multiset.add("bar");
    assertEquals(3, multiset.size());
    assertEquals(2, multiset.count("foo"));
  }

  public void testCreateFromIterable() {

    super(
        Arrays.asList(ConstructionPathway.values()),
        n -> n * Math.log(n),
        ImmutableList.of(
            QueryOp.create(
                "count",
                (ms, o) -> {
                  int unused = ms.count(o);
                },
                Math::log)));
  }

  /** All the ways to create an ImmutableMultiset. */
  enum ConstructionPathway implements Construction<Multiset<Object>> {

  /** Number of bits used to store the numbers of hash table bits (max 30). */
  private static final int HASH_TABLE_BITS_MAX_BITS = 5;

  /** Use high bits of metadata for modification count. */
  static final int MODIFICATION_COUNT_INCREMENT = (1 << HASH_TABLE_BITS_MAX_BITS);

  /** Bitmask that selects the low bits of metadata to get hashTableBits. */
  static final int HASH_TABLE_BITS_MASK = (1 << HASH_TABLE_BITS_MAX_BITS) - 1;

  /** Number of bits used to store the numbers of hash table bits (max 30). */
  private static final int HASH_TABLE_BITS_MAX_BITS = 5;

  /** Use high bits of metadata for modification count. */
  static final int MODIFICATION_COUNT_INCREMENT = (1 << HASH_TABLE_BITS_MAX_BITS);

  /** Bitmask that selects the low bits of metadata to get hashTableBits. */
  static final int HASH_TABLE_BITS_MASK = (1 << HASH_TABLE_BITS_MAX_BITS) - 1;

    for (int i = 0; i < reps; i++) {
      // TODO(b/145386688): This access should be guarded by 'this.segment', which is not currently
      // held
      segment.removeEntryFromChain(chain, head);
      dummy += segment.count;
    }
    return dummy;
  }

  }

  @Override
  public Set<E> edgesConnecting(N node) {
    return new MultiEdgesConnecting<E>(incidentEdgeMap, node) {
      @Override
      public int size() {
        return adjacentNodesMultiset().count(node);
      }
    };
  }

  @Override
  @CheckForNull
  public N removeInEdge(E edge, boolean isSelfLoop) {
    if (!isSelfLoop) {
      return removeOutEdge(edge);
    }
    return null;
  }