}
    return false;
  }

  @Override
  public boolean replace(K key, V oldValue, V newValue) {
    if (oldValue.equals(get(key))) {
      alertListenerIfPresent(key, oldValue, RemovalCause.REPLACED);
      put(key, newValue);
      return true;
    }
    return false;
  }

  @Override
  public V replace(K key, V value) {
    V currentValue = get(key);
    if (currentValue != null) {

    }
  }

  // Returned from removeAt() to iterator.remove()
  static class MoveDesc<E> {
    final E toTrickle;
    final E replaced;

    MoveDesc(E toTrickle, E replaced) {
      this.toTrickle = toTrickle;
      this.replaced = replaced;
    }
  }

  /** Removes and returns the value at {@code index}. */
  private E removeAndGet(int index) {
    E value = elementData(index);

    // If duplicates are allowed, this map will track the last value for each duplicated key.
    // A second pass will retain only the first entry for that key, but with this last value. The
    // value will then be replaced by null, signaling that later entries with the same key should
    // be deleted.
    Map<K, @Nullable V> duplicates = null;
    int dupCount = 0;
    for (int i = 0; i < n; i++) {

              || countMap.replace(element, existingCounter, newCounter);
        }
      } else {
        if (existingCounter.compareAndSet(oldValue, newCount)) {
          if (newCount == 0) {
            // Just CASed to 0; remove the entry to clean up the map. If the removal fails,
            // another thread has already replaced it with a new counter, which is fine.

              || countMap.replace(element, existingCounter, newCounter);
        }
      } else {
        if (existingCounter.compareAndSet(oldValue, newCount)) {
          if (newCount == 0) {
            // Just CASed to 0; remove the entry to clean up the map. If the removal fails,
            // another thread has already replaced it with a new counter, which is fine.

    map.put(one, three);
    assertNotified(listener, one, two, RemovalCause.REPLACED);

    Map<Object, Object> newMap = ImmutableMap.of(one, four);
    map.putAll(newMap);
    assertNotified(listener, one, three, RemovalCause.REPLACED);

    map.replace(one, five);
    assertNotified(listener, one, four, RemovalCause.REPLACED);

    map.replace(one, five, six);
    assertNotified(listener, one, five, RemovalCause.REPLACED);

    map.put(one, three);
    assertNotified(listener, one, two, RemovalCause.REPLACED);

    Map<Object, Object> newMap = ImmutableMap.of(one, four);
    map.putAll(newMap);
    assertNotified(listener, one, three, RemovalCause.REPLACED);

    map.replace(one, five);
    assertNotified(listener, one, four, RemovalCause.REPLACED);

    map.replace(one, five, six);
    assertNotified(listener, one, five, RemovalCause.REPLACED);

   * href="http://tools.ietf.org/html/rfc3548#section-3">RFC 3548</a>.)
   *
   * <p>The character {@code '='} is used for padding, but can be {@linkplain #omitPadding()
   * omitted} or {@linkplain #withPadChar(char) replaced}.
   *
   * <p>No line feeds are added by default, as per <a
   * href="http://tools.ietf.org/html/rfc4648#section-3.1">RFC 4648 section 3.1</a>, Line Feeds in

   *
   * <p>If {@code values} is empty, this is equivalent to {@link #removeAll(Object) removeAll(key)}.
   *
   * @return the collection of replaced values, or an empty collection if no values were previously
   *     associated with the key. The collection <i>may</i> be modifiable, but updating it will have
   *     no effect on the multimap.
   */

   * generated by applying {@code function} to the elements of {@code fromSpliterator}. (If {@code
   * function} returns {@code null} for an input, it is replaced with an empty stream.)
   */
  static <InElementT extends @Nullable Object> Spliterator.OfInt flatMapToInt(
      Spliterator<InElementT> fromSpliterator,