* Concatenates values to a destination list, avoiding duplicates.
     * @param dest The destination list.
     * @param newValues The new values to add.
     * @param <T> The type of the values.
     */
    protected static <T> void concatValues(final List<T> dest, final T... newValues) {
        for (final T value : newValues) {
            if (!dest.contains(value)) {
                dest.add(value);
            }
        }
    }

      @ParametricNullness K key,
      boolean containedKey,
      @Nullable V oldValue,
      @ParametricNullness V newValue) {
    if (containedKey) {
      // The cast is safe because of the containedKey check.
      removeFromInverseMap(uncheckedCastNullableTToT(oldValue));
    }
    inverse.delegate.put(newValue, key);
  }

  @CanIgnoreReturnValue
  @Override
  public @Nullable V remove(@Nullable Object key) {

   *
   * @param currentValue the current value (of either base or a cell)
   * @param newValue the argument from a user update call
   * @return result of the update function
   */
  abstract long fn(long currentValue, long newValue);

  /**
   * Handles cases of updates involving initialization, resizing, creating new Cells, and/or

    List<V> oldValues = getCopy(key);
    ListIterator<V> keyValues = new ValueForKeyIterator(key);
    Iterator<? extends V> newValues = values.iterator();

    // Replace existing values, if any.
    while (keyValues.hasNext() && newValues.hasNext()) {
      keyValues.next();
      keyValues.set(newValues.next());
    }

    // Remove remaining old values, if any.
    while (keyValues.hasNext()) {
      keyValues.next();

   *
   * @param currentValue the current value (of either base or a cell)
   * @param newValue the argument from a user update call
   * @return result of the update function
   */
  abstract long fn(long currentValue, long newValue);

  /**
   * Handles cases of updates involving initialization, resizing, creating new Cells, and/or

  }

  @CanIgnoreReturnValue
  @Override
  public boolean replace(K key, @Nullable V oldValue, V newValue) {
    checkNotNull(key);
    checkNotNull(newValue);
    if (oldValue == null) {
      return false;
    }
    int hash = hash(key);
    return segmentFor(hash).replace(key, hash, oldValue, newValue);
  }

  @CanIgnoreReturnValue
  @Override
  public @Nullable V replace(K key, V value) {

  }

  private static void insertIntoReplica(Map<Integer, AtomicInteger> replica, int newValue) {
    if (replica.containsKey(newValue)) {
      replica.get(newValue).incrementAndGet();
    } else {
      replica.put(newValue, new AtomicInteger(1));
    }
  }

  private static void removeMinFromReplica(
      SortedMap<Integer, AtomicInteger> replica, int minValue) {

    List<V> oldValues = getCopy(key);
    ListIterator<V> keyValues = new ValueForKeyIterator(key);
    Iterator<? extends V> newValues = values.iterator();

    // Replace existing values, if any.
    while (keyValues.hasNext() && newValues.hasNext()) {
      keyValues.next();
      keyValues.set(newValues.next());
    }

    // Remove remaining old values, if any.
    while (keyValues.hasNext()) {
      keyValues.next();

    return (K) keys[index];
  }

  int getValue(int index) {
    checkElementIndex(index, size);
    return values[index];
  }

  void setValue(int index, int newValue) {
    checkElementIndex(index, size);
    values[index] = newValue;
  }

  Entry<K> getEntry(int index) {
    checkElementIndex(index, size);
    return new MapEntry(index);
  }

  @CollectionSize.Require(absent = ZERO)
  public void testComputeIfAbsent_nullTreatedAsAbsent() {
    initMapWithNullValue();
    assertEquals(
        "computeIfAbsent(presentAssignedToNull, function) should return newValue",
        getValueForNullKey(),
        getMap()
            .computeIfAbsent(
                getKeyForNullValue(),
                k -> {
                  assertEquals(getKeyForNullValue(), k);