// ordering.reverse() might be optimized, so let it do its thing
    return ordering.<T>reverse().<@NonNull S>nullsLast();
  }

  @SuppressWarnings("unchecked") // still need the right way to explain this
  @Override
  public <S extends @Nullable T> Ordering<@Nullable S> nullsFirst() {
    return (Ordering<@Nullable S>) this;
  }

  @Override

  private static final Iterable<@Nullable Integer> iterableNull = Arrays.asList((Integer) null);
  private static final Iterable<@Nullable Integer> iterableNullNull =
      Arrays.asList((Integer) null, null);
  private static final Iterable<@Nullable Integer> iterableNull1 = Arrays.asList(null, 1);
  private static final Iterable<@Nullable Integer> iterable1Null = Arrays.asList(1, null);

              }

              @Override
              public boolean equals(@Nullable Object o) {
                return map.equals(o);
              }

              @Override
              public String toString() {
                return map.toString();
              }

              @Override
              public @Nullable String remove(Object key) {
                return map.remove(key);
              }

      List<@Nullable String> listWithNulls = asList("a", null, "b");
      assertThrows(NullPointerException.class, () -> builder.addAll((List<String>) listWithNulls));
    }

    {
      ImmutableMultiset.Builder<String> builder = ImmutableMultiset.builder();
      Multiset<@Nullable String> multisetWithNull =
          LinkedHashMultiset.create(Arrays.<@Nullable String>asList("a", null, "b"));

  public void testTransformEntrySetContains() {
    Map<@Nullable String, @Nullable Boolean> underlying = new HashMap<>();
    underlying.put("a", null);
    underlying.put("b", true);
    underlying.put(null, true);

    Map<@Nullable String, @Nullable Boolean> map =
        transformValues(
            underlying,
            new Function<@Nullable Boolean, @Nullable Boolean>() {
              @Override

 *
 * @author Kevin Bourrillion
 * @since 2.0
 */
@GwtCompatible
@FunctionalInterface
public interface Function<F extends @Nullable Object, T extends @Nullable Object>
    extends java.util.function.Function<F, T> {
  @Override
  @ParametricNullness
  T apply(@ParametricNullness F input);

  /**

 *             object being processed or any application-specific state information. May be null if no
 *             additional data is needed.
 */
public record RequestTrace(
        @Nullable String context,
        @Nullable RequestTrace parent,
        @Nullable Object data) {

    public static final String CONTEXT_PLUGIN = "plugin";
    public static final String CONTEXT_PROJECT = "project";

   *
   * @since 33.2.0 (available since 22.0 in guava-jre)
   */
  @IgnoreJRERequirement // Users will use this only if they're already using streams.
  public static <T extends @Nullable Object, E extends @Nullable Object, M extends Multiset<E>>
      Collector<T, ?, M> toMultiset(
          Function<? super T, E> elementFunction,
          ToIntFunction<? super T> countFunction,
          Supplier<M> multisetSupplier) {

   *
   * <p>To collect to an {@link ImmutableMultiset}, use {@link
   * ImmutableMultiset#toImmutableMultiset}.
   *
   * @since 22.0
   */
  public static <T extends @Nullable Object, E extends @Nullable Object, M extends Multiset<E>>
      Collector<T, ?, M> toMultiset(
          Function<? super T, E> elementFunction,
          ToIntFunction<? super T> countFunction,
          Supplier<M> multisetSupplier) {

            MultimapBuilder.linkedHashKeys().linkedHashSetValues()::<K, V>build),
        ImmutableSetMultimap::copyOf);
  }

  static <
          T extends @Nullable Object,
          K extends @Nullable Object,
          V extends @Nullable Object,
          M extends Multimap<K, V>>
      Collector<T, ?, M> toMultimap(
          Function<? super T, ? extends K> keyFunction,