public static <K, V> ImmutableSortedMap<K, V> copyOfSorted(SortedMap<K, ? extends V> map) {
    Comparator<? super K> comparator = map.comparator();
    if (comparator == null) {
      // If map has a null comparator, the keys should have a natural ordering,
      // even though K doesn't explicitly implement Comparable.
      comparator = (Comparator<? super K>) NATURAL_ORDER;
    }
    if (map instanceof ImmutableSortedMap) {

    @Override
    protected List<String> create(String[] elements) {
      Comparator<String> comparator = createExplicitComparator(elements);
      ImmutableSet<String> set = ImmutableSortedSet.copyOf(comparator, asList(elements));
      return set.asList();
    }
  }

   * there is no need to use this method.
   *
   * @param comparator the comparator that defines the order
   * @return comparator itself if it is already an {@code Ordering}; otherwise an ordering that
   *     wraps that comparator
   */
  @GwtCompatible(serializable = true)
  public static <T extends @Nullable Object> Ordering<T> from(Comparator<T> comparator) {
    return (comparator instanceof Ordering)
        ? (Ordering<T>) comparator

  public void testOrderedByComparator() {
    Comparator<? super K> comparator = navigableMap.comparator();
    if (comparator == null) {
      comparator =
          new Comparator<K>() {
            @SuppressWarnings("unchecked")
            @Override
            public int compare(K o1, K o2) {
              return ((Comparable) o1).compareTo(o2);
            }
          };
    }

/**
 * Tests for {@code Comparators}.
 *
 * @author Louis Wasserman
 */
@GwtCompatible
@ElementTypesAreNonnullByDefault
public class ComparatorsTest extends TestCase {
  public void testLexicographical() {
    Comparator<String> comparator = Ordering.natural();
    Comparator<Iterable<String>> lexy = Comparators.lexicographical(comparator);

    ImmutableList<String> empty = ImmutableList.of();

       * provided but a row Comparator isn't, cellSet() iterates across the rows in the first
       * column, the rows in the second column, etc.
       */
      Comparator<Cell<R, C, V>> comparator =
          (Cell<R, C, V> cell1, Cell<R, C, V> cell2) -> {
            int rowCompare =
                (rowComparator == null)
                    ? 0

     */
    private static final int UNSET_EXPECTED_SIZE = -1;

    private final Comparator<B> comparator;
    private int expectedSize = UNSET_EXPECTED_SIZE;
    private int maximumSize = Integer.MAX_VALUE;

    private Builder(Comparator<B> comparator) {
      this.comparator = checkNotNull(comparator);
    }

    /**

   * there is no need to use this method.
   *
   * @param comparator the comparator that defines the order
   * @return comparator itself if it is already an {@code Ordering}; otherwise an ordering that
   *     wraps that comparator
   */
  @GwtCompatible(serializable = true)
  public static <T extends @Nullable Object> Ordering<T> from(Comparator<T> comparator) {
    return (comparator instanceof Ordering)
        ? (Ordering<T>) comparator

  public static <K, V> ImmutableSortedMap<K, V> copyOfSorted(SortedMap<K, ? extends V> map) {
    Comparator<? super K> comparator = map.comparator();
    if (comparator == null) {
      // If map has a null comparator, the keys should have a natural ordering,
      // even though K doesn't explicitly implement Comparable.
      comparator = (Comparator<? super K>) NATURAL_ORDER;
    }
    if (map instanceof ImmutableSortedMap) {

  private final Comparator<? super C> columnComparator;

  private static class Factory<C, V> implements Supplier<Map<C, V>>, Serializable {
    final Comparator<? super C> comparator;

    Factory(Comparator<? super C> comparator) {
      this.comparator = comparator;
    }

    @Override
    public Map<C, V> get() {
      return new TreeMap<>(comparator);
    }