import java.util.logging.Logger;
import org.jspecify.annotations.Nullable;

/** A holder for a {@link Logger} that is initialized only when requested. */
@GwtCompatible
final class LazyLogger {
  private final Object lock = new Object();

  private final String loggerName;
  private volatile @Nullable Logger logger;

  LazyLogger(Class<?> ownerOfLogger) {
    this.loggerName = ownerOfLogger.getName();

import java.util.Set;
import org.jspecify.annotations.NullMarked;
import org.jspecify.annotations.Nullable;

/**
 * Creates sets, containing sample elements, to be tested.
 *
 * @author Kevin Bourrillion
 */
@GwtCompatible
@NullMarked
public interface TestSetGenerator<E extends @Nullable Object> extends TestCollectionGenerator<E> {
  @Override
  Set<E> create(Object... elements);

   * @return a {@code BloomFilter}
   * @since 19.0
   */
  public static <T extends @Nullable Object> BloomFilter<T> create(
      Funnel<? super T> funnel, long expectedInsertions, double fpp) {
    return create(funnel, expectedInsertions, fpp, BloomFilterStrategies.MURMUR128_MITZ_64);
  }

  @VisibleForTesting
  static <T extends @Nullable Object> BloomFilter<T> create(

    public CustomScheduler() {}

    /** A callable class that can reschedule itself using a {@link CustomScheduler}. */
    private final class ReschedulableCallable implements Callable<@Nullable Void> {

      /** The underlying task. */
      private final Runnable wrappedRunnable;

      /** The executor on which this Callable will be scheduled. */
      private final ScheduledExecutorService executor;

import java.lang.annotation.Inherited;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.util.Collection;
import java.util.Set;
import org.jspecify.annotations.Nullable;

/**
 * When describing the features of the collection produced by a given generator (i.e. in a call to
 * {@link
 * com.google.common.collect.testing.FeatureSpecificTestSuiteBuilder#withFeatures(Feature...)}),

import java.lang.annotation.Inherited;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.util.Collection;
import java.util.Set;
import org.jspecify.annotations.Nullable;

/**
 * When describing the features of the collection produced by a given generator (i.e. in a call to
 * {@link
 * com.google.common.collect.testing.FeatureSpecificTestSuiteBuilder#withFeatures(Feature...)}),

import org.jspecify.annotations.NullMarked;
import org.jspecify.annotations.Nullable;

/**
 * Creates multisets, containing sample elements, to be tested.
 *
 * @author Jared Levy
 */
@GwtCompatible
@NullMarked
public interface TestMultisetGenerator<E extends @Nullable Object>
    extends TestCollectionGenerator<E> {
  @Override
  Multiset<E> create(Object... elements);

  @Override
  public Optional<V> edgeValue(N nodeU, N nodeV) {
    return Optional.ofNullable(edgeValueOrDefault(nodeU, nodeV, null));
  }

  @Override
  public Optional<V> edgeValue(EndpointPair<N> endpoints) {
    return Optional.ofNullable(edgeValueOrDefault(endpoints, null));
  }

  @Override
  public final boolean equals(@Nullable Object obj) {
    if (obj == this) {
      return true;
    }

import com.google.common.annotations.GwtIncompatible;
import com.google.common.annotations.J2ktIncompatible;
import java.lang.ref.ReferenceQueue;
import java.lang.ref.WeakReference;
import org.jspecify.annotations.Nullable;

/**
 * Weak reference with a {@code finalizeReferent()} method which a background thread invokes after
 * the garbage collector reclaims the referent. This is a simpler alternative to using a {@link
 * ReferenceQueue}.

import com.google.common.annotations.GwtCompatible;
import com.google.common.collect.testing.features.CollectionSize;
import java.util.Collection;
import org.jspecify.annotations.NullMarked;
import org.jspecify.annotations.Nullable;

/**
 * The subject-generator interface accepted by Collection testers, for testing a Collection at one
 * particular {@link CollectionSize}.
 *