assertEquals(6, queue.size());
    assertEquals(8, queue.capacity());
    checkUnbounded(queue);
    checkNatural(queue);
  }

  public void testCreation_maximumSize_withContents() {
    MinMaxPriorityQueue<Integer> queue =
        rawtypeToWildcard(MinMaxPriorityQueue.maximumSize(42)).create(NUMBERS);
    assertEquals(6, queue.size());
    assertEquals(11, queue.capacity());
    assertEquals(42, queue.maximumSize);

  /**
   * Constructs a new finalizable phantom reference.
   *
   * @param referent to phantom reference
   * @param queue that should finalize the referent
   */
  protected FinalizablePhantomReference(@Nullable T referent, FinalizableReferenceQueue queue) {
    super(referent, queue.queue);
    queue.cleanUp();
  }

  private final BlockingQueue<HttpUrl> queue;
  private final ConcurrentHashMap<String, AtomicInteger> hostnames = new ConcurrentHashMap<>();
  private final int hostLimit;

  public Crawler(OkHttpClient client, int queueLimit, int hostLimit) {
    this.client = client;
    this.queue = new LinkedBlockingQueue<>(queueLimit);
    this.hostLimit = hostLimit;
  }

            : new DirectStarter();
  }

  /** The actual reference queue that our background thread will poll. */
  final ReferenceQueue<Object> queue;

  final PhantomReference<Object> frqRef;

  /** Whether or not the background thread started successfully. */
  final boolean threadStarted;

  /** Constructs a new queue. */
  public FinalizableReferenceQueue() {

package com.google.common.collect.testing.testers;

import com.google.common.annotations.GwtCompatible;
import com.google.common.collect.testing.AbstractCollectionTester;
import java.util.Queue;
import org.junit.Ignore;

/**
 * Base class for queue collection tests.
 *
 * @author Jared Levy
 */
@GwtCompatible
@Ignore("test runners must not instantiate and run this directly, only via suites we build")

package com.google.common.collect.testing.testers;

import com.google.common.annotations.GwtCompatible;
import com.google.common.collect.testing.AbstractCollectionTester;
import java.util.Queue;
import org.junit.Ignore;

/**
 * Base class for queue collection tests.
 *
 * @author Jared Levy
 */
@GwtCompatible
@Ignore("test runners must not instantiate and run this directly, only via suites we build")

  @CanIgnoreReturnValue
  public static Set<Feature<?>> addImpliedFeatures(Set<Feature<?>> features) {
    Queue<Feature<?>> queue = new ArrayDeque<>(features);
    while (!queue.isEmpty()) {
      Feature<?> feature = queue.remove();
      for (Feature<?> implied : feature.getImpliedFeatures()) {
        if (features.add(implied)) {
          queue.add(implied);
        }
      }
    }
    return features;
  }

  /**

  @CanIgnoreReturnValue
  public static Set<Feature<?>> addImpliedFeatures(Set<Feature<?>> features) {
    Queue<Feature<?>> queue = new ArrayDeque<>(features);
    while (!queue.isEmpty()) {
      Feature<?> feature = queue.remove();
      for (Feature<?> implied : feature.getImpliedFeatures()) {
        if (features.add(implied)) {
          queue.add(implied);
        }
      }
    }
    return features;
  }

  /**

        assertTrue(fesenClient.prepareSearch("fess_crawler.queue")
                .setQuery(QueryBuilders.termQuery("sessionId", "id1"))
                .execute()
                .actionGet()
                .getHits()
                .getTotalHits()
                .value() > 0);
        assertTrue(fesenClient.prepareSearch("fess_crawler.queue")
                .setQuery(QueryBuilders.termQuery("sessionId", "id2"))

        .testForwarding(
            Queue.class,
            new Function<Queue, Queue>() {
              @Override
              public Queue apply(Queue delegate) {
                return wrap(delegate);
              }
            });
  }

  private static <T> Queue<T> wrap(Queue<T> delegate) {
    return new ForwardingQueue<T>() {
      @Override
      protected Queue<T> delegate() {
        return delegate;