loadFinalizer(new SystemLoader(), new DecoupledLoader(), new DirectLoader());
    startFinalizer = getStartFinalizer(finalizer);
  }

  /** 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;

        loadFinalizer(new SystemLoader(), new DecoupledLoader(), new DirectLoader());
    startFinalizer = getStartFinalizer(finalizer);
  }

  /** 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;

    public boolean offer(T o) {
      return standardOffer(o);
    }

    @Override
    public @Nullable T peek() {
      return standardPeek();
    }

    @Override
    public @Nullable T poll() {
      return standardPoll();
    }
  }

  public static Test suite() {
    TestSuite suite = new TestSuite();

    suite.addTestSuite(ForwardingQueueTest.class);
    suite.addTest(

        assertFalse(map.containsValue(valueOne));
        assertNull(map.get(keyOne));
        assertEquals(1, map.size());
        assertNull(segment.getKeyReferenceQueueForTesting().poll());
      }
    }
  }

  public void testDrainValueReferenceQueueOnWrite() {
    for (MapMaker maker : allWeakValueStrengthMakers()) {

        assertFalse(map.containsValue(valueOne));
        assertNull(map.get(keyOne));
        assertEquals(1, map.size());
        assertNull(segment.getKeyReferenceQueueForTesting().poll());
      }
    }
  }

  public void testDrainValueReferenceQueueOnWrite() {
    for (MapMaker maker : allWeakValueStrengthMakers()) {

  @CanIgnoreReturnValue
  @Override
  public @Nullable E poll() {
    final Monitor monitor = this.monitor;
    if (monitor.enterIf(notEmpty)) {
      try {
        return extract();
      } finally {
        monitor.leave();
      }
    } else {
      return null;
    }
  }

  @CanIgnoreReturnValue
  @Override
  public @Nullable E poll(long timeout, TimeUnit unit) throws InterruptedException {

    assertEquals(0, queue.size());

    try {
      queue.element();
      fail();
    } catch (NoSuchElementException expected) {
    }

    assertNull(queue.peek());
    assertNull(queue.poll());
    try {
      queue.remove();
      fail();
    } catch (NoSuchElementException expected) {
    }
  }

  public void testRemainingCapacity_maxSize0() {

    assertEquals(0, queue.size());

    try {
      queue.element();
      fail();
    } catch (NoSuchElementException expected) {
    }

    assertNull(queue.peek());
    assertNull(queue.poll());
    try {
      queue.remove();
      fail();
    } catch (NoSuchElementException expected) {
    }
  }

  public void testRemainingCapacity_maxSize0() {

   */
  protected void startUp() throws Exception {}

  /**
   * Run the service. This method is invoked on the execution thread. Implementations must respond
   * to stop requests. You could poll for lifecycle changes in a work loop:
   *
   * <pre>
   *   public void run() {
   *     while ({@link #isRunning()}) {
   *       // perform a unit of work
   *     }
   *   }
   * </pre>
   *

      // If even the first one wasn't there, clean up so that the next test doesn't see an element.
      producerThread.cancel(true);
      producer.doneProducing.await();
      if (drained == 0) {
        q.poll(); // not necessarily there if producer was interrupted
      }
    }
  }

  public void testZeroElements() throws Exception {
    for (BlockingQueue<Object> q : blockingQueues()) {
      testZeroElements(q);