} else {
        return (NavigableMap<K, V>) super.createSubMap(map, firstExclusive, lastExclusive);
      }
    }
  }

  @Override
  public NavigableMapTestSuiteBuilder<K, V> newBuilderUsing(
      TestSortedMapGenerator<K, V> delegate, Bound to, Bound from) {
    return subSuiteUsing(new NavigableMapSubmapTestMapGenerator<K, V>(delegate, to, from));
  }