assertNull(map.get(keyOne));
        assertEquals(1, map.size());
        assertNull(segment.keyReferenceQueue.poll());
      }
    }
  }

  public void testDrainValueReferenceQueueOnWrite() {
    for (CacheBuilder<Object, Object> builder : allKeyValueStrengthMakers()) {
      LocalCache<Object, Object> map = makeLocalCache(builder.concurrencyLevel(1));
      if (map.usesValueReferences()) {