/**
 * GWT implementation of {@link ImmutableSet} that forwards to another {@code Set} implementation.
 *
 * @author Hayward Chan
 */
@ElementTypesAreNonnullByDefault
@SuppressWarnings("serial") // Serialization only done in GWT.
public abstract class ForwardingImmutableSet<E> extends ImmutableSet<E> {
  private final transient Set<E> delegate;

  ForwardingImmutableSet(Set<E> delegate) {

import java.util.HashMap;

/**
 * GWT emulation of {@link RegularImmutableBiMap}.
 *
 * @author Jared Levy
 * @author Hayward Chan
 */
@ElementTypesAreNonnullByDefault
@SuppressWarnings("serial")
class RegularImmutableBiMap<K, V> extends ImmutableBiMap<K, V> {
  static final RegularImmutableBiMap<Object, Object> EMPTY =
      new RegularImmutableBiMap<Object, Object>();

import com.google.common.annotations.J2ktIncompatible;
import javax.annotation.CheckForNull;

/**
 * A descending wrapper around an {@code ImmutableSortedMultiset}
 *
 * @author Louis Wasserman
 */
@SuppressWarnings("serial") // uses writeReplace, not default serialization
@GwtIncompatible
@ElementTypesAreNonnullByDefault
final class DescendingImmutableSortedMultiset<E> extends ImmutableSortedMultiset<E> {

import com.google.common.annotations.J2ktIncompatible;
import javax.annotation.CheckForNull;

/**
 * A descending wrapper around an {@code ImmutableSortedMultiset}
 *
 * @author Louis Wasserman
 */
@SuppressWarnings("serial") // uses writeReplace, not default serialization
@GwtIncompatible
@ElementTypesAreNonnullByDefault
final class DescendingImmutableSortedMultiset<E> extends ImmutableSortedMultiset<E> {

/**
 * Implementation of {@link ImmutableSet} with exactly one element.
 *
 * @author Kevin Bourrillion
 * @author Nick Kralevich
 */
@GwtCompatible(serializable = true, emulated = true)
@SuppressWarnings("serial") // uses writeReplace(), not default serialization
@ElementTypesAreNonnullByDefault
final class SingletonImmutableSet<E> extends ImmutableSet<E> {
  // We deliberately avoid caching the asList and hashCode here, to ensure that with

/**
 * Implementation of {@link ImmutableMultiset} with zero or more elements.
 *
 * @author Jared Levy
 * @author Louis Wasserman
 */
@GwtCompatible(emulated = true, serializable = true)
@SuppressWarnings("serial") // uses writeReplace(), not default serialization
@ElementTypesAreNonnullByDefault
class RegularImmutableMultiset<E> extends ImmutableMultiset<E> {
  static final RegularImmutableMultiset<Object> EMPTY =

import java.util.function.Predicate;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * GWT emulated version of {@link ImmutableCollection}.
 *
 * @author Jesse Wilson
 */
@SuppressWarnings("serial") // we're overriding default serialization
@ElementTypesAreNonnullByDefault
public abstract class ImmutableCollection<E> extends AbstractCollection<E> implements Serializable {
  static final int SPLITERATOR_CHARACTERISTICS =

   * tasks. Second, the returned list will always be empty, as any submitted task is considered to
   * have started execution. This applies also to tasks given to {@code invokeAll} or {@code
   * invokeAny} which are pending serial execution, even the subset of the tasks that have not yet
   * started execution. It is unclear from the {@code ExecutorService} specification if these should

 * single-element sorted set.
 *
 * @author Jared Levy
 * @author Louis Wasserman
 */
@GwtCompatible(serializable = true, emulated = true)
@SuppressWarnings({"serial", "rawtypes"})
@ElementTypesAreNonnullByDefault
final class RegularImmutableSortedSet<E> extends ImmutableSortedSet<E> {
  static final RegularImmutableSortedSet<Comparable> NATURAL_EMPTY_SET =

  private interface Sample {
    String sleepThenReturnInput(String input);

    void sleepThenThrowException() throws SampleException;
  }

  @SuppressWarnings("serial")
  private static class SampleException extends Exception {}

  @SuppressWarnings("serial")
  private static class SampleRuntimeException extends RuntimeException {}

  private static class SampleImpl implements Sample {
    final long delayMillis;