/**
 * Simple benchmark: create, start, read. This does not currently report the most useful result
 * because it's ambiguous to what extent the stopwatch benchmark is being affected by GC.
 *
 * @author Kevin Bourrillion
 */
@NullUnmarked
public class StopwatchBenchmark {
  @Benchmark
  long stopwatch(int reps) {
    long total = 0;
    for (int i = 0; i < reps; i++) {
      Stopwatch s = Stopwatch.createStarted();

import com.google.common.base.Preconditions;
import org.jspecify.annotations.Nullable;

/**
 * Implementation of {@link ImmutableSet} with exactly one element.
 *
 * @author Kevin Bourrillion
 * @author Nick Kralevich
 */
@GwtCompatible
@SuppressWarnings("serial") // uses writeReplace(), not default serialization
final class SingletonImmutableSet<E> extends ImmutableSet<E> {

import java.util.function.BiConsumer;
import org.jspecify.annotations.Nullable;

/**
 * Implementation of {@link ImmutableMap} with exactly one entry.
 *
 * @author Jesse Wilson
 * @author Kevin Bourrillion
 */
@GwtCompatible
@SuppressWarnings("serial") // uses writeReplace(), not default serialization
final class SingletonImmutableBiMap<K, V> extends ImmutableBiMap<K, V> {

  final transient K singleKey;

/**
 * Simple benchmark: create, start, read. This does not currently report the most useful result
 * because it's ambiguous to what extent the stopwatch benchmark is being affected by GC.
 *
 * @author Kevin Bourrillion
 */
@NullUnmarked
public class StopwatchBenchmark {
  @Benchmark
  long stopwatch(int reps) {
    long total = 0;
    for (int i = 0; i < reps; i++) {
      Stopwatch s = Stopwatch.createStarted();

import java.util.Spliterator;
import java.util.function.Consumer;
import org.jspecify.annotations.Nullable;

/**
 * {@code keySet()} implementation for {@link ImmutableMap}.
 *
 * @author Jesse Wilson
 * @author Kevin Bourrillion
 */
@GwtCompatible
final class ImmutableMapKeySet<K, V> extends IndexedImmutableSet<K> {
  private final ImmutableMap<K, V> map;

  ImmutableMapKeySet(ImmutableMap<K, V> map) {
    this.map = map;
  }

import java.util.Map;
import junit.framework.Test;

/**
 * Tests the {@link Map} implementations of {@link java.util}, suppressing tests that trip known
 * bugs in OpenJDK 6 or higher.
 *
 * @author Kevin Bourrillion
 */
// TODO(cpovirk): consider renaming this class in light of our now running it under newer JDKs.
@AndroidIncompatible // test-suite builders
public class OpenJdk6MapTests extends TestsForMapsInJavaUtil {

import java.util.concurrent.TimeUnit;
import java.util.logging.Logger;
import org.jspecify.annotations.NullUnmarked;

/**
 * Utilities for performing thread interruption in tests
 *
 * @author Kevin Bourrillion
 * @author Chris Povirk
 */
@NullUnmarked
final class InterruptionUtil {
  private static final Logger logger = Logger.getLogger(InterruptionUtil.class.getName());

 *
 * <p>See the Guava User Guide article on <a
 * href="https://github.com/google/guava/wiki/FunctionalExplained">the use of {@code Predicate}</a>.
 *
 * @author Kevin Bourrillion
 * @since 2.0
 */
@FunctionalInterface
@GwtCompatible
public interface Predicate<T extends @Nullable Object> extends java.util.function.Predicate<T> {
  /**

import java.io.Serializable;
import org.jspecify.annotations.Nullable;

/**
 * {@code keySet()} implementation for {@link ImmutableMap}.
 *
 * @author Jesse Wilson
 * @author Kevin Bourrillion
 */
@GwtCompatible
final class ImmutableMapKeySet<K, V> extends IndexedImmutableSet<K> {
  private final ImmutableMap<K, V> map;

  ImmutableMapKeySet(ImmutableMap<K, V> map) {
    this.map = map;
  }

import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.util.HashMap;
import org.jspecify.annotations.Nullable;

/**
 * Multiset implementation backed by a {@link HashMap}.
 *
 * @author Kevin Bourrillion
 * @author Jared Levy
 * @since 2.0
 */
@GwtCompatible
public final class HashMultiset<E extends @Nullable Object> extends AbstractMapBasedMultiset<E> {