@Override
  public synchronized int lookup(int key,
                                 @NotNull ValueAcceptor valuesAcceptor) throws IOException {
    HashMapSegmentLayout segment = segmentForKey(key);

    return hashMapAlgo.lookup(segment, key, valuesAcceptor);
  }
@Override
  public synchronized int lookup(int key,
                                 @NotNull ValueAcceptor valuesAcceptor)