if (result == null) {
      inverse =
          result =
              new JdkBackedImmutableBiMap<>(
                  new InverseEntries(), backwardDelegate, forwardDelegate);
      result.inverse = this;
    }
    return result;
  }

  @WeakOuter
  private final class InverseEntries extends ImmutableList<Entry<V, K>> {
    @Override
    public Entry<V, K> get(int index) {
      Entry<K, V> entry = entries.get(index);