try {
            if (cells == as) { // Expand table unless stale
              Cell[] rs = new Cell[n << 1];
              for (int i = 0; i < n; ++i) rs[i] = as[i];
              cells = rs;
            }
          } finally {
            busy = 0;
          }
          collide = false;
          continue; // Retry with expanded table
        }
        h ^= h << 13; // Rehash

  /**
   * Given a set of features, add to it all the features directly or indirectly implied by any of
   * them, and return it.
   *
   * @param features the set of features to expand
   * @return the same set of features, expanded with all implied features
   */
  @CanIgnoreReturnValue
  public static Set<Feature<?>> addImpliedFeatures(Set<Feature<?>> features) {
    Queue<Feature<?>> queue = new ArrayDeque<>(features);

    }.start();

    // give the second get a chance to run; it is okay for this to be racy
    // as the end result should be the same either way
    thirdSignal.await();
    Thread.yield();

    // Expand!
    CacheTesting.forceExpandSegment(cache, key);

    // start another waiting thread
    new Thread() {
      @Override
      public void run() {
        fourthSignal.countDown();

          try {
            if (cells == as) { // Expand table unless stale
              Cell[] rs = new Cell[n << 1];
              for (int i = 0; i < n; ++i) rs[i] = as[i];
              cells = rs;
            }
          } finally {
            busy = 0;
          }
          collide = false;
          continue; // Retry with expanded table
        }
        h ^= h << 13; // Rehash

        && ipString.charAt(ipString.length() - 2) != IPV6_DELIMITER) {
      return null; // :$ requires ::$
    }
    if (hasSkip && partsSkipped <= 0) {
      return null; // :: must expand to at least one '0'
    }
    if (!hasSkip && delimiterCount + 1 != IPV6_PART_COUNT) {
      return null; // Incorrect number of parts
    }

    ByteBuffer rawBytes = ByteBuffer.allocate(2 * IPV6_PART_COUNT);

    oldValueRef.clear();
    assertNull(segment.put(key, hash, newValue, true));
    assertEquals(1, segment.count);
    assertSame(newValue, segment.get(key, hash));
  }

  public void testSegmentPut_expand() {
    LocalCache<Object, Object> map =
        makeLocalCache(createCacheBuilder().concurrencyLevel(1).initialCapacity(1));
    Segment<Object, Object> segment = map.segments[0];

    oldValueRef.clear();
    assertNull(segment.put(key, hash, newValue, true));
    assertEquals(1, segment.count);
    assertSame(newValue, segment.get(key, hash));
  }

  public void testSegmentPut_expand() {
    LocalCache<Object, Object> map =
        makeLocalCache(createCacheBuilder().concurrencyLevel(1).initialCapacity(1));
    Segment<Object, Object> segment = map.segments[0];

    }.start();

    // give the second get a chance to run; it is okay for this to be racy
    // as the end result should be the same either way
    thirdSignal.await();
    Thread.yield();

    // Expand!
    CacheTesting.forceExpandSegment(cache, key);

    // start another waiting thread
    new Thread() {
      @Override
      public void run() {
        fourthSignal.countDown();

      Java8Compatibility.clear(buf);
    }
    return total;
  }

  /** Max array length on JVM. */
  private static final int MAX_ARRAY_LEN = Integer.MAX_VALUE - 8;

  /** Large enough to never need to expand, given the geometric progression of buffer sizes. */
  private static final int TO_BYTE_ARRAY_DEQUE_SIZE = 20;

  /**
   * Returns a byte array containing the bytes from the buffers already in {@code bufs} (which have

        evictEntries(newEntry);
        return null;
      } finally {
        unlock();
        postWriteCleanup();
      }
    }

    /** Expands the table if possible. */
    @GuardedBy("this")
    void expand() {
      AtomicReferenceArray<ReferenceEntry<K, V>> oldTable = table;
      int oldCapacity = oldTable.length();
      if (oldCapacity >= MAXIMUM_CAPACITY) {
        return;