* <? extends Object> is mostly the same as <?> to plain Java. But to nullness checkers, they
   * differ: <? extends Object> means "non-null types," while <?> means "all types."
   */
  ImmutableMap<K, V> getAllPresent(Iterable<? extends Object> keys);

  /**
   * Associates {@code value} with {@code key} in this cache. If the cache previously contained a
   * value associated with {@code key}, the old value is replaced by {@code value}.
   *

    runIteratorTest(UNMODIFIABLE, IteratorTester.KnownOrder.UNKNOWN_ORDER, getSampleElements());
  }

  private void runIteratorTest(
      Set<IteratorFeature> features, IteratorTester.KnownOrder knownOrder, Iterable<E> elements) {
    new IteratorTester<E>(
        Platform.collectionIteratorTesterNumIterations(), features, elements, knownOrder) {
      @Override
      protected Iterator<E> newTargetIterator() {

  public EquivalenceTester<T> addEquivalenceGroup(T first, T... rest) {
    addEquivalenceGroup(Lists.asList(first, rest));
    return this;
  }

  @CanIgnoreReturnValue
  public EquivalenceTester<T> addEquivalenceGroup(Iterable<T> group) {
    delegate.addRelatedGroup(group);
    items.addAll(ImmutableList.copyOf(group));
    return this;
  }

  /** Run tests on equivalence methods, throwing a failure on an invalid test */

    }

    @Override
    public E[] createArray(int length) {
      return gen.createArray(length);
    }

    @Override
    public Iterable<E> order(List<E> insertionOrder) {
      return gen.order(insertionOrder);
    }
  }

  private static Set<Feature<?>> computeReserializedCollectionFeatures(Set<Feature<?>> features) {

  public EquivalenceTester<T> addEquivalenceGroup(T first, T... rest) {
    addEquivalenceGroup(Lists.asList(first, rest));
    return this;
  }

  @CanIgnoreReturnValue
  public EquivalenceTester<T> addEquivalenceGroup(Iterable<T> group) {
    delegate.addRelatedGroup(group);
    items.addAll(ImmutableList.copyOf(group));
    return this;
  }

  /** Run tests on equivalence methods, throwing a failure on an invalid test */

 * @author Louis Wasserman
 */
@GwtCompatible
@NullMarked
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();
    ImmutableList<String> a = ImmutableList.of("a");
    ImmutableList<String> aa = ImmutableList.of("a", "a");

  }

  @MapFeature.Require(SUPPORTS_PUT)
  public void testPutAll_nullCollectionReference() {
    assertThrows(NullPointerException.class, () -> getMap().putAll(null));
  }

  private void putAll(Iterable<Entry<K, V>> entries) {
    Map<K, V> map = new LinkedHashMap<>();
    for (Entry<K, V> entry : entries) {
      map.put(entry.getKey(), entry.getValue());
    }
    getMap().putAll(map);
  }

  /**

 *
 * {@snippet :
 * class MySubtypeTests extends SubtypeTester {
 *   @TestSubtype(suppressGetSubtype = true, suppressGetSupertype = true)
 *   public <T> Iterable<? extends T> listIsSubtypeOfIterable(List<T> list) {
 *     return isSubtype(list);
 *   }
 *
 *   @TestSubtype
 *   public List<String> intListIsNotSubtypeOfStringList(List<Integer> intList) {

      return new SampleElements<>(1, 4, 3, 2, 5);
    }

    @Override
    public Integer[] createArray(int length) {
      return new Integer[length];
    }

    @Override
    public Iterable<Integer> order(List<Integer> insertionOrder) {
      return Ordering.natural().sortedCopy(insertionOrder);
    }

    @Override
    public Set<Integer> create(Object... elements) {

    @Override
    @SuppressWarnings("unchecked")
    public Entry<Class, Impl>[] createArray(int length) {
      return (Entry<Class, Impl>[]) new Entry<?, ?>[length];
    }

    @Override
    public Iterable<Entry<Class, Impl>> order(List<Entry<Class, Impl>> insertionOrder) {
      return insertionOrder;
    }
  }

  private interface One {}

  private interface Two {}

  private interface Three {}