@Override
    public boolean equals(@Nullable Object o) {
      return false;
    }

    @Override
    public int hashCode() {
      return super.hashCode();
    }
  }

  /** Test class that returns true if the test object is null */
  private static class InvalidEqualsNullObject {

    @Override
    public boolean equals(@Nullable Object o) {
      return o == this || o == null;
    }

 *             object being processed or any application-specific state information. May be null if no
 *             additional data is needed.
 */
public record RequestTrace(
        @Nullable String context,
        @Nullable RequestTrace parent,
        @Nullable Object data) {

    public static final String CONTEXT_PLUGIN = "plugin";
    public static final String CONTEXT_PROJECT = "project";

import org.jspecify.annotations.Nullable;

/**
 * Basic implementation of {@code Multiset<E>} backed by an instance of {@code Map<E, Count>}.
 *
 * <p>For serialization to work, the subclass must specify explicit {@code readObject} and {@code
 * writeObject} methods.
 *
 * @author Kevin Bourrillion
 */
@GwtCompatible
abstract class AbstractMapBasedMultiset<E extends @Nullable Object> extends AbstractMultiset<E>

@GwtCompatible
@J2ktIncompatible
public final class EnumHashBiMap<K extends Enum<K>, V extends @Nullable Object>
    extends AbstractBiMap<K, V> {
  transient Class<K> keyTypeOrObjectUnderJ2cl;

  /**
   * Returns a new, empty {@code EnumHashBiMap} using the specified key type.
   *
   * @param keyType the key type
   */
  public static <K extends Enum<K>, V extends @Nullable Object> EnumHashBiMap<K, V> create(
      Class<K> keyType) {

     */
    <T> boolean replace(@Nonnull Key<T> key, @Nullable T oldValue, @Nullable T newValue);

    /**
     * Gets the session data associated with the specified key.
     *
     * @param key the key for which to retrieve the session data, must not be {@code null}
     * @return the session data associated with the key or {@code null} if none
     */
    @Nullable
    <T> T get(@Nonnull Key<T> key);

    /**

  }

  public void testNullFriendlyTransform() {
    Iterator<@Nullable Integer> input = Arrays.<@Nullable Integer>asList(1, 2, null, 3).iterator();
    Iterator<String> result =
        Iterators.transform(
            input,
            new Function<@Nullable Integer, String>() {
              @Override
              public String apply(@Nullable Integer from) {
                return String.valueOf(from);
              }

    return (prefix & ~mask) | (suffix & mask);
  }

  static int remove(
      @Nullable Object key,
      @Nullable Object value,
      int mask,
      Object table,
      int[] entries,
      @Nullable Object[] keys,
      @Nullable Object @Nullable [] values) {
    int hash = smearedHash(key);
    int tableIndex = hash & mask;
    int next = tableGet(table, tableIndex);

import java.util.concurrent.Executor;
import java.util.concurrent.FutureTask;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.TimeoutException;
import org.jspecify.annotations.Nullable;

/**
 * A {@link FutureTask} that also implements the {@link ListenableFuture} interface. Unlike {@code
 * FutureTask}, {@code ListenableFutureTask} does not provide an overrideable {@link

    checkNotNull(valueComparator);
    return Comparator.<Optional<T>, @Nullable T>comparing(
        o -> orElseNull(o), Comparator.nullsLast(valueComparator));
  }

  // For discussion of why this exists, see the Android flavor.
  private static <T> @Nullable T orElseNull(Optional<T> optional) {
    return optional.orElse(null);
  }

  /**

  }

  public boolean containsKey(@Nullable Object key) {
    return indexOf(key) != -1;
  }

  public int get(@Nullable Object key) {
    int index = indexOf(key);
    return (index == -1) ? 0 : values[index];
  }

  @CanIgnoreReturnValue
  public int remove(@Nullable Object key) {
    return remove(key, smearedHash(key));
  }

  private int remove(@Nullable Object key, int hash) {