@GwtCompatible
public abstract class ForwardingSet<E extends @Nullable Object> extends ForwardingCollection<E>
    implements Set<E> {
  // TODO(lowasser): identify places where thread safety is actually lost

  /** Constructor for use by subclasses. */
  protected ForwardingSet() {}

  @Override
  protected abstract Set<E> delegate();

  @Override
  public boolean equals(@Nullable Object object) {

  enum TriState {
    FALSE,
    MAYBE,
    TRUE,
  }

  static class Foo {
    private final String aString;
    private final int anInt;
    private final @Nullable TriState anEnum;

    Foo(String aString, int anInt, @Nullable TriState anEnum) {
      this.aString = aString;
      this.anInt = anInt;
      this.anEnum = anEnum;
    }

    @Override
    public String toString() {

  @Deprecated
  protected UncheckedExecutionException(@Nullable String message) {
    super(message);
  }

  /**
   * Creates a new instance with the given detail message and cause. Prefer to provide a
   * non-nullable {@code cause}, as many users expect to find one.
   */
  public UncheckedExecutionException(@Nullable String message, @Nullable Throwable cause) {
    super(message, cause);
  }

  /**

import java.util.SortedMap;
import org.jspecify.annotations.NullMarked;
import org.jspecify.annotations.Nullable;

/**
 * Creates sorted maps, containing sample elements, to be tested.
 *
 * @author Louis Wasserman
 */
@GwtCompatible
@NullMarked
public interface TestSortedMapGenerator<K extends @Nullable Object, V extends @Nullable Object>
    extends TestMapGenerator<K, V> {
  @Override
  SortedMap<K, V> create(Object... elements);

    IntegerDomain() {
      super(true);
    }

    @Override
    public @Nullable Integer next(Integer value) {
      int i = value;
      return (i == Integer.MAX_VALUE) ? null : i + 1;
    }

    @Override
    public @Nullable Integer previous(Integer value) {
      int i = value;
      return (i == Integer.MIN_VALUE) ? null : i - 1;
    }

    @Override

import java.util.concurrent.ScheduledFuture;
import org.jspecify.annotations.Nullable;

/**
 * Helper interface to implement both {@link ListenableFuture} and {@link ScheduledFuture}.
 *
 * @author Anthony Zana
 * @since 15.0
 */
@GwtCompatible
public interface ListenableScheduledFuture<V extends @Nullable Object>

import java.util.Collection;
import org.jspecify.annotations.NullMarked;
import org.jspecify.annotations.Nullable;

/**
 * Creates collections, containing sample elements, to be tested.
 *
 * @author Kevin Bourrillion
 */
@GwtCompatible
@NullMarked
public interface TestCollectionGenerator<E extends @Nullable Object>

  private static final class NewExecutionListQueue {
    static final Logger log = Logger.getLogger(NewExecutionListQueue.class.getName());

    @GuardedBy("this")
    private @Nullable RunnableExecutorPair head;

    @GuardedBy("this")
    private @Nullable RunnableExecutorPair tail;

    @GuardedBy("this")
    private boolean executed;

    void add(Runnable runnable, Executor executor) {

   * @since 28.1
   */
  @Deprecated
  @Override
  @DoNotCall("Always throws UnsupportedOperationException")
  public final void merge(
      Range<K> range,
      @Nullable V value,
      BiFunction<? super V, ? super @Nullable V, ? extends @Nullable V> remappingFunction) {
    throw new UnsupportedOperationException();
  }

  @Override
  public ImmutableMap<Range<K>, V> asMapOfRanges() {
    if (ranges.isEmpty()) {

   *
   * @since 15.0
   */
  public static <E extends @Nullable Object> Funnel<Iterable<? extends E>> sequentialFunnel(
      Funnel<E> elementFunnel) {
    return new SequentialFunnel<>(elementFunnel);
  }

  private static final class SequentialFunnel<E extends @Nullable Object>
      implements Funnel<Iterable<? extends E>> {
    private final Funnel<E> elementFunnel;