@J2ktIncompatible // serialization
        @GwtIncompatible // serialization
        Object writeReplace() {
          return super.writeReplace();
        }
      }
      return new EntrySetImpl();
    }

    @Override
    ImmutableCollection<V> createValues() {
      return new ImmutableMapValues<>(this);
    }

    // redeclare to help optimizers with b/310253115