E entry = (E) ref;
        map.reclaimKey(entry);
        if (++i == DRAIN_MAX) {
          break;
        }
      }
    }

    @GuardedBy("this")
    void drainValueReferenceQueue(ReferenceQueue<V> valueReferenceQueue) {
      Reference<? extends V> ref;
      int i = 0;
      while ((ref = valueReferenceQueue.poll()) != null) {
        @SuppressWarnings("unchecked")