* the least recently used element is removed.
 * </p>
 * @author shinsuke
 * @param <E> the type of elements maintained by this set
 */
public class LruHashSet<E> extends AbstractSet<E> implements Set<E>, java.io.Serializable {
    private static final long serialVersionUID = 1L;

    /**
     * The internal LRU hash map used to store elements.
     */
    private final LruHashMap<E, Object> map;

import com.google.errorprone.annotations.concurrent.LazyInit;
import com.google.j2objc.annotations.RetainedWith;
import java.io.InvalidObjectException;
import java.io.ObjectInputStream;
import java.io.Serializable;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Iterator;
import java.util.List;
import java.util.NoSuchElementException;
import java.util.Set;
import java.util.stream.Collector;

import com.google.errorprone.annotations.DoNotCall;
import com.google.errorprone.annotations.concurrent.LazyInit;
import java.io.InvalidObjectException;
import java.io.ObjectInputStream;
import java.io.Serializable;
import java.util.Arrays;
import java.util.Collection;
import java.util.Collections;
import java.util.Comparator;
import java.util.Iterator;
import java.util.NavigableSet;
import java.util.SortedSet;

    return outer;
  }

  private static final class TestQueue<E> implements Queue<E> {
    private final Queue<E> delegate = new LinkedList<>();
    private final Object mutex = new Object[0]; // something Serializable

    @Override
    public boolean offer(E o) {
      assertTrue(Thread.holdsLock(mutex));
      return delegate.offer(o);
    }

    @Override
    public @Nullable E poll() {

import com.google.common.annotations.GwtCompatible;
import com.google.common.annotations.GwtIncompatible;
import com.google.common.annotations.J2ktIncompatible;
import com.google.errorprone.annotations.InlineMe;
import java.io.Serializable;
import java.util.AbstractList;
import java.util.Arrays;
import java.util.Collection;
import java.util.Collections;
import java.util.Comparator;
import java.util.List;
import java.util.RandomAccess;

import com.google.common.annotations.GwtCompatible;
import com.google.common.base.Preconditions;
import com.google.errorprone.annotations.CanIgnoreReturnValue;
import com.google.errorprone.annotations.Immutable;
import java.io.Serializable;
import java.util.AbstractList;
import java.util.Arrays;
import java.util.Collection;
import java.util.List;
import java.util.RandomAccess;
import java.util.Spliterator;
import java.util.Spliterators;

import com.google.errorprone.annotations.CanIgnoreReturnValue;
import com.google.j2objc.annotations.WeakOuter;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.Serializable;
import java.util.Collection;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.ConcurrentMap;

    suite.addTest(
        BiMapTestSuiteBuilder.using(new ImmutableBiMapGenerator())
            .named("ImmutableBiMap")
            .withFeatures(
                CollectionSize.ANY,
                CollectionFeature.SERIALIZABLE,
                CollectionFeature.KNOWN_ORDER,
                MapFeature.REJECTS_DUPLICATES_AT_CREATION,
                MapFeature.ALLOWS_ANY_NULL_QUERIES)

            .withFeatures(ALLOWS_ANY_NULL_QUERIES, SERIALIZABLE, KNOWN_ORDER, CollectionSize.ANY)
            .createTestSuite());
    suite.addTest(
        ListMultimapTestSuiteBuilder.using(new ImmutableListMultimapCopyOfEntriesGenerator())
            .named("ImmutableListMultimap.copyOf[Iterable<Entry>]")
            .withFeatures(ALLOWS_ANY_NULL_QUERIES, SERIALIZABLE, KNOWN_ORDER, CollectionSize.ANY)
            .createTestSuite());

import com.google.errorprone.annotations.concurrent.LazyInit;
import com.google.j2objc.annotations.WeakOuter;
import java.io.InvalidObjectException;
import java.io.ObjectInputStream;
import java.io.Serializable;
import java.util.Arrays;
import java.util.Collection;
import java.util.Collections;
import java.util.Iterator;
import java.util.List;
import java.util.function.Function;
import java.util.function.ToIntFunction;