docs: public void closeSegmentKeyValueRegistration() throws IOException {
      if (!closed) {
        if (segmentRegistration != null) {
          Map<String, T1> keyValueList = segmentKeyValueList.get(segmentName);
          T1 tmpSegmentValueBoundary = segmentValuesBoundary.get(segmentName);
          for (Entry<String, T1> entry : keyValueList.entrySet()) {
            if (tmpSegmentValueBoundary == null || compareWithBoundary(
                entry.getValue(), tmpSegmentValueBoundary)) {
              segmentKeys.add(entry.getKey());
            }
          }
        }
      } else {
        throw new IOException("already closed");
      }
    }