* an example, see {@link ForwardingCollection}.
 *
 * <h2>Other</h2>
 *
 * <ul>
 *   <li>{@link EvictingQueue}
 *   <li>{@link Interner}, {@link Interners}
 *   <li>{@link MapMaker}
 *   <li>{@link MinMaxPriorityQueue}
 *   <li>{@link PeekingIterator}
 * </ul>
 */
@CheckReturnValue
@NullMarked
package com.google.common.collect;

  @J2ktIncompatible // MapMaker
  public static Ordering<@Nullable Object> arbitrary() {
    return ArbitraryOrderingHolder.ARBITRARY_ORDERING;
  }

  @J2ktIncompatible // MapMaker
  private static final class ArbitraryOrderingHolder {
    static final Ordering<@Nullable Object> ARBITRARY_ORDERING = new ArbitraryOrdering();
  }

  @J2ktIncompatible // MapMaker
  @VisibleForTesting

  @J2ktIncompatible // MapMaker
  public static Ordering<@Nullable Object> arbitrary() {
    return ArbitraryOrderingHolder.ARBITRARY_ORDERING;
  }

  @J2ktIncompatible // MapMaker
  private static final class ArbitraryOrderingHolder {
    static final Ordering<@Nullable Object> ARBITRARY_ORDERING = new ArbitraryOrdering();
  }

  @J2ktIncompatible // MapMaker
  @VisibleForTesting

    @J2ktIncompatible // java.io.ObjectInputStream
    private void readObject(ObjectInputStream in) throws IOException, ClassNotFoundException {
      in.defaultReadObject();
      MapMaker mapMaker = readMapMaker(in);
      delegate = mapMaker.makeMap();
      readEntries(in);
    }

    private Object readResolve() {
      return delegate;
    }
  }

     */
    final Map<LockGraphNode, ExampleStackTrace> allowedPriorLocks =
        new MapMaker().weakKeys().makeMap();

    /**
     * The map tracking lock nodes that can cause a lock acquisition cycle if acquired before this
     * node.
     */
    final Map<LockGraphNode, PotentialDeadlockException> disallowedPriorLocks =
        new MapMaker().weakKeys().makeMap();

    final String lockName;

       * UnsignedBytesBenchmark. TODO(cpovirk): benchmark this
       */
      /*
       * A CopyOnWriteArraySet<WeakReference> is faster than a newSetFromMap of a MapMaker map with
       * weakKeys() and concurrencyLevel(1), even up to at least 12 cached exception types.
       */
      private static final Set<WeakReference<Class<? extends Exception>>> validClasses =

@J2ktIncompatible
@GwtIncompatible
public class FinalizableReferenceQueue implements Closeable {
  /*
   * The Finalizer thread keeps a phantom reference to this object. When the client (for example, a
   * map built by MapMaker) no longer has a strong reference to this object, the garbage collector
   * will reclaim it and enqueue the phantom reference. The enqueued reference will trigger the
   * Finalizer to stop.
   *

import com.google.common.base.MoreObjects;
import com.google.common.base.Preconditions;
import com.google.common.base.Supplier;
import com.google.common.collect.ImmutableList;
import com.google.common.collect.MapMaker;
import com.google.common.math.IntMath;
import com.google.common.primitives.Ints;
import java.lang.ref.Reference;
import java.lang.ref.ReferenceQueue;
import java.lang.ref.WeakReference;
import java.math.RoundingMode;

@J2ktIncompatible
@GwtIncompatible
public class FinalizableReferenceQueue implements Closeable {
  /*
   * The Finalizer thread keeps a phantom reference to this object. When the client (for example, a
   * map built by MapMaker) no longer has a strong reference to this object, the garbage collector
   * will reclaim it and enqueue the phantom reference. The enqueued reference will trigger the
   * Finalizer to stop.
   *

 * <p>This implementation is heavily derived from revision 1.96 of <a
 * href="http://tinyurl.com/ConcurrentHashMap">ConcurrentHashMap.java</a>.
 *
 * @author Charles Fry
 * @author Bob Lee ({@code com.google.common.collect.MapMaker})
 * @author Doug Lea ({@code ConcurrentHashMap})
 */
@SuppressWarnings({
  "GoodTime", // lots of violations (nanosecond math)
  "nullness", // too much trouble for the payoff
})
@GwtCompatible