guava/src/com/google/common/collect/ImmutableRangeMap.java
public static <K extends Comparable<?>, V> ImmutableRangeMap<K, V> of(Range<K> range, V value) {
    return new ImmutableRangeMap<>(ImmutableList.of(range), ImmutableList.of(value));
  }
public static <K extends Comparable<?>, V> ImmutableRangeMap<K, V> of(Range<K> range, V value) {
    return new ImmutableRangeMap<>(ImmutableList.of(range), ImmutableList.of(value));
  }
Returns an immutable range map mapping a single range to a single value.