public static <C extends Comparable> ImmutableRangeSet<C> copyOf(RangeSet<C> rangeSet) {
    checkNotNull(rangeSet);
    if (rangeSet.isEmpty()) {
      return of();
    } else if (rangeSet.encloses(Range.all())) {
      return all();
    }

    if (rangeSet instanceof ImmutableRangeSet) {
      ImmutableRangeSet<C> immutableRangeSet = (ImmutableRangeSet<C>) rangeSet;
      if (!immutableRangeSet.isPartialView()) {

  @GwtIncompatible
  private static final Collector<Range<Comparable<?>>, ?, ImmutableRangeSet<Comparable<?>>>
      TO_IMMUTABLE_RANGE_SET =
          Collector.of(
              ImmutableRangeSet::builder,
              ImmutableRangeSet.Builder::add,
              ImmutableRangeSet.Builder::combine,
              ImmutableRangeSet.Builder::build);

  // Lists

  @SuppressWarnings({"rawtypes", "unchecked"})

  @GwtIncompatible
  private static final Collector<Range<Comparable<?>>, ?, ImmutableRangeSet<Comparable<?>>>
      TO_IMMUTABLE_RANGE_SET =
          Collector.of(
              ImmutableRangeSet::builder,
              ImmutableRangeSet.Builder::add,
              ImmutableRangeSet.Builder::combine,
              ImmutableRangeSet.Builder::build);

  // Lists

  @SuppressWarnings({"rawtypes", "unchecked"})

FIELD com.google.common.collect.ConcurrentHashMultiset.countMap
FIELD com.google.common.collect.ImmutableMultiset.asList
FIELD com.google.common.collect.ImmutableRangeMap.ranges
FIELD com.google.common.collect.ImmutableRangeSet.ranges
FIELD com.google.common.collect.ImmutableSet.asList
FIELD com.google.common.collect.JdkBackedImmutableBiMap.inverse
FIELD com.google.common.collect.Maps.FilteredMapValues.unfiltered

        return TreeRangeSet.create(contents);
      }
    },
    ImmutableRangeSetImpl {
      @Override
      <K extends Comparable<K>> RangeSet<K> create(RangeSet<K> contents) {
        return ImmutableRangeSet.copyOf(contents);
      }
    };

    abstract <K extends Comparable<K>> RangeSet<K> create(RangeSet<K> contents);
  }

  public enum SetMultimapImpl {
    HashMultimapImpl {
      @Override

      if (view.encloses(restriction)) {
        return this;
      } else if (view.isConnected(restriction)) {
        return new SubRangeSet(restriction.intersection(view));
      } else {
        return ImmutableRangeSet.of();
      }
    }
  }