* PeekingIterator#remove()} removes the same elements as the reference's iterator {@code
   * remove()}.
   */
  private static class PeekingIteratorTester<T extends @Nullable Object> extends IteratorTester<T> {
    private final Iterable<T> master;
    private @Nullable List<T> targetList;

    PeekingIteratorTester(Collection<T> master) {
      super(master.size() + 3, MODIFIABLE, master, IteratorTester.KnownOrder.KNOWN_ORDER);

import java.io.Closeable;
import java.io.IOException;
import java.io.InputStream;
import java.io.Reader;
import java.util.logging.Level;
import java.util.logging.Logger;
import org.jspecify.annotations.Nullable;

/**
 * Utility methods for working with {@link Closeable} objects.
 *
 * @author Michael Lancaster
 * @since 1.0
 */
@J2ktIncompatible
@GwtIncompatible
public final class Closeables {

  abstract void describeAsLowerBound(StringBuilder sb);

  abstract void describeAsUpperBound(StringBuilder sb);

  abstract @Nullable C leastValueAbove(DiscreteDomain<C> domain);

  abstract @Nullable C greatestValueBelow(DiscreteDomain<C> domain);

  /*
   * The canonical form is a BelowValue cut whenever possible, otherwise ABOVE_ALL, or

   * elements and to build again.
   *
   * @since 2.0
   */
  public static class Builder<E> extends ImmutableCollection.ArrayBasedBuilder<E> {
    @VisibleForTesting @Nullable Object @Nullable [] hashTable;
    private int hashCode;

    /**
     * Creates a new builder. The returned builder is equivalent to the builder generated by {@link
     * ImmutableSet#builder}.
     */

// @Ignore affects the Android test runner, which respects JUnit 4 annotations on JUnit 3 tests.
@SuppressWarnings("JUnit4ClassUsedInJUnit3")
@NullMarked
public class MultimapEqualsTester<K extends @Nullable Object, V extends @Nullable Object>
    extends AbstractMultimapTester<K, V, Multimap<K, V>> {
  public void testEqualsTrue() {
    new EqualsTester()
        .addEqualityGroup(multimap(), getSubjectGenerator().create(getSampleElements().toArray()))

  public Set<E> edgesConnecting(EndpointPair<N> endpoints) {
    return delegate().edgesConnecting(endpoints);
  }

  @Override
  public @Nullable E edgeConnectingOrNull(N nodeU, N nodeV) {
    return delegate().edgeConnectingOrNull(nodeU, nodeV);
  }

  @Override
  public @Nullable E edgeConnectingOrNull(EndpointPair<N> endpoints) {
    return delegate().edgeConnectingOrNull(endpoints);
  }

  @Override

import java.util.Iterator;
import java.util.NoSuchElementException;
import junit.framework.AssertionFailedError;
import junit.framework.TestCase;
import org.jspecify.annotations.NullMarked;
import org.jspecify.annotations.Nullable;

/** Tests for {@link AbstractSequentialIterator}. */
@GwtCompatible
@NullMarked
public class AbstractSequentialIteratorTest extends TestCase {
  @GwtIncompatible // Too slow
  public void testDoublerExhaustive() {

import com.google.common.annotations.J2ktIncompatible;
import java.io.Serializable;
import java.util.Iterator;
import org.jspecify.annotations.Nullable;

/** An ordering that uses the reverse of a given order. */
@GwtCompatible
final class ReverseOrdering<T extends @Nullable Object> extends Ordering<T>
    implements Serializable {
  final Ordering<? super T> forwardOrder;

  ReverseOrdering(Ordering<? super T> forwardOrder) {

 * footprint.
 */
@GwtCompatible
@NullMarked
final class ObjectCountLinkedHashMap<K extends @Nullable Object> extends ObjectCountHashMap<K> {
  /** Creates an empty {@code ObjectCountLinkedHashMap} instance. */
  static <K extends @Nullable Object> ObjectCountLinkedHashMap<K> create() {
    return new ObjectCountLinkedHashMap<K>();
  }

  /**

import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.atomic.AtomicReference;
import junit.framework.TestCase;
import org.jspecify.annotations.NullUnmarked;
import org.jspecify.annotations.Nullable;

/**
 * Unit test for {@link AbstractCache}.
 *
 * @author Charles Fry
 */
@NullUnmarked
public class AbstractCacheTest extends TestCase {

  public void testGetIfPresent() {