@SuppressWarnings("JUnit4ClassUsedInJUnit3")
@NullMarked
public abstract class AbstractMultimapTester<
        K extends @Nullable Object, V extends @Nullable Object, M extends Multimap<K, V>>
    extends AbstractContainerTester<M, Entry<K, V>> {

  private M multimap;

  protected M multimap() {
    return multimap;
  }

  /**

// @Ignore affects the Android test runner, which respects JUnit 4 annotations on JUnit 3 tests.
@SuppressWarnings("JUnit4ClassUsedInJUnit3")
@NullMarked
public class MapPutAllTester<K extends @Nullable Object, V extends @Nullable Object>
    extends AbstractMapTester<K, V> {
  private List<Entry<K, V>> containsNullKey;
  private List<Entry<K, V>> containsNullValue;

  @Override
  public void setUp() throws Exception {

import java.util.Map.Entry;
import org.jspecify.annotations.NullMarked;
import org.jspecify.annotations.Nullable;

/**
 * Creates multimaps, containing sample elements, to be tested.
 *
 * @author Louis Wasserman
 */
@GwtCompatible
@NullMarked
public interface TestMultimapGenerator<
        K extends @Nullable Object, V extends @Nullable Object, M extends Multimap<K, V>>
    extends TestContainerGenerator<M, Entry<K, V>> {

import java.util.Map.Entry;
import org.jspecify.annotations.NullMarked;
import org.jspecify.annotations.Nullable;

/**
 * Creates multimaps, containing sample elements, to be tested.
 *
 * @author Louis Wasserman
 */
@GwtCompatible
@NullMarked
public interface TestMultimapGenerator<
        K extends @Nullable Object, V extends @Nullable Object, M extends Multimap<K, V>>
    extends TestContainerGenerator<M, Entry<K, V>> {

 */
@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;
  }

import com.google.common.annotations.J2ktIncompatible;
import java.util.concurrent.Callable;
import java.util.concurrent.ScheduledExecutorService;
import java.util.concurrent.ScheduledFuture;
import java.util.concurrent.TimeUnit;
import org.jspecify.annotations.Nullable;

/**
 * An abstract {@code ScheduledExecutorService} that allows subclasses to {@linkplain
 * #wrapTask(Callable) wrap} tasks before they are submitted to the underlying executor.
 *

   * range [0, k) and ignore the remaining elements.
   */
  private final @Nullable T[] buffer;
  private int bufferSize;

  /**
   * The largest of the lowest k elements we've seen so far relative to this comparator. If
   * bufferSize ≥ k, then we can ignore any elements greater than this value.
   */
  private @Nullable T threshold;

@GwtIncompatible
interface ReferenceEntry<K, V> {
  /** Returns the value reference from this entry. */
  @Nullable ValueReference<K, V> getValueReference();

  /** Sets the value reference for this entry. */
  void setValueReference(ValueReference<K, V> valueReference);

  /** Returns the next entry in the chain. */
  @Nullable ReferenceEntry<K, V> getNext();

  /** Returns the entry's hash. */
  int getHash();

import java.util.Iterator;
import org.jspecify.annotations.Nullable;

/**
 * An iterator that transforms a backing iterator; for internal use. This avoids the object overhead
 * of constructing a {@link com.google.common.base.Function Function} for internal methods.
 *
 * @author Louis Wasserman
 */
@GwtCompatible
abstract class TransformedIterator<F extends @Nullable Object, T extends @Nullable Object>
    implements Iterator<T> {

   *
   * <p><b>{@code Stream} equivalent:</b> {@code Stream.empty()}.
   *
   * @since 20.0
   */
  @SuppressWarnings("EmptyList") // ImmutableList doesn't support nullable element types
  public static <E extends @Nullable Object> FluentIterable<E> of() {
    return FluentIterable.from(Collections.<E>emptyList());
  }

  /**
   * Returns a fluent iterable containing the specified elements in order.
   *