CountDownLatch isInterruptibleRegistered = new CountDownLatch(1);
    SlowChannel slowChannel = new SlowChannel();
    InterruptibleTask<@Nullable Void> task =
        new InterruptibleTask<@Nullable Void>() {
          @Override
          @Nullable Void runInterruptibly() throws Exception {
            slowChannel.doBegin();
            isInterruptibleRegistered.countDown();
            try {

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

@GwtCompatible
final class PairwiseEquivalence<E, T extends @Nullable E> extends Equivalence<Iterable<T>>
    implements Serializable {
  final Equivalence<E> elementEquivalence;

  PairwiseEquivalence(Equivalence<E> elementEquivalence) {

// @Ignore affects the Android test runner, which respects JUnit 4 annotations on JUnit 3 tests.
@SuppressWarnings("JUnit4ClassUsedInJUnit3")
@NullMarked
public class AbstractListMultimapTester<K extends @Nullable Object, V extends @Nullable Object>
    extends AbstractMultimapTester<K, V, ListMultimap<K, V>> {

  @Override
  protected void assertGet(K key, V... values) {
    assertGet(key, asList(values));
  }

  @Override

import java.util.concurrent.CountDownLatch;
import java.util.concurrent.atomic.AtomicBoolean;
import junit.framework.TestCase;
import org.jspecify.annotations.NullUnmarked;
import org.jspecify.annotations.Nullable;

/**
 * Tests for {@link GcFinalization}.
 *
 * @author Martin Buchholz
 * @author mike nonemacher
 */

@NullUnmarked
public class GcFinalizationTest extends TestCase {

import com.google.common.annotations.GwtCompatible;
import com.google.errorprone.annotations.CanIgnoreReturnValue;
import java.util.NoSuchElementException;
import org.jspecify.annotations.Nullable;

/**
 * This class provides a skeletal implementation of the {@code Iterator} interface, to make this
 * interface easier to implement for certain types of data sources.
 *

  @Override
  public E takeLast() throws InterruptedException {
    return delegate().takeLast();
  }

  @Override
  public @Nullable E pollFirst(long timeout, TimeUnit unit) throws InterruptedException {
    return delegate().pollFirst(timeout, unit);
  }

  @Override
  public @Nullable E pollLast(long timeout, TimeUnit unit) throws InterruptedException {
    return delegate().pollLast(timeout, unit);
  }

  @Override

@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) {

      new IteratorOperation() {
        @Override
        public @Nullable Object execute(Iterator<?> iterator) {
          iterator.remove();
          return null;
        }
      };

  private static final IteratorOperation NEXT_METHOD =
      new IteratorOperation() {
        @Override
        public @Nullable Object execute(Iterator<?> iterator) {
          return iterator.next();
        }

 */
@NullUnmarked
public class StringCatcher {
  private final List<String> events = new ArrayList<>();

  @Subscribe
  public void hereHaveAString(@Nullable String string) {
    events.add(string);
  }

  public void methodWithoutAnnotation(@Nullable String string) {
    Assert.fail("Event bus must not call methods without @Subscribe!");
  }

  public List<String> getEvents() {
    return events;
  }

   *
   * @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;