* partially collected.
   */
  @Nullable ReferenceEntry<K, V> getEntry(@Nullable Object key) {
    // does not impact recency ordering
    if (key == null) {
      return null;
    }
    int hash = hash(key);
    return segmentFor(hash).getEntry(key, hash);
  }

  void refresh(K key) {
    int hash = hash(checkNotNull(key));

   * partially collected.
   */
  @Nullable ReferenceEntry<K, V> getEntry(@Nullable Object key) {
    // does not impact recency ordering
    if (key == null) {
      return null;
    }
    int hash = hash(key);
    return segmentFor(hash).getEntry(key, hash);
  }

  void refresh(K key) {
    int hash = hash(checkNotNull(key));

      for (int i = 0; i < SMALL_MAX_SIZE; i++) {
        Object key = new Object();
        int hash = map.hash(key);

        map.get(key, loader);
        ReferenceEntry<Object, Object> entry = segment.getEntry(key, hash);
        writeOrder.add(entry);
        readOrder.add(entry);
      }

      checkEvictionQueues(map, segment, readOrder, writeOrder);
      checkExpirationTimes(map);

      for (int i = 0; i < SMALL_MAX_SIZE; i++) {
        Object key = new Object();
        int hash = map.hash(key);

        map.get(key, loader);
        ReferenceEntry<Object, Object> entry = segment.getEntry(key, hash);
        writeOrder.add(entry);
        readOrder.add(entry);
      }

      checkEvictionQueues(map, segment, readOrder, writeOrder);
      checkExpirationTimes(map);