code: private static <K, V> ImmutableSortedMap<K, V> fromEntries(
        Comparator<? super K> comparator,
        boolean sameComparator,
        Iterable<? extends Entry<? extends K, ? extends V>> entries) {
      // "adding" type params to an array of a raw type should be safe as
      // long as no one can ever cast that same array instance back to a
      // raw type.
      @SuppressWarnings("unchecked")
      Entry<K, V>[] entryArray = (Entry[]) Iterables.toArray(entries, EMPTY_ENTRY_ARRAY);
      return fromEntries(comparator, sameComparator, entryArray, entryArray.length);
    }
docs: Accepts a collection of possibly-null entries. If {@code sameComparator}, then it is assumed
  that they do not need to be sorted or checked for dupes.