static IndexReader wrap(IndexReader reader) throws IOException {
  LeafReader[] leafReaders = reader.leaves().stream()
      .map(LeafReaderContext::reader)
      .map(TermVectorReusingLeafReader::new)
      .toArray(LeafReader[]::new);
  return new BaseCompositeReader<IndexReader>(leafReaders) {
    @Override
    protected void doClose() throws IOException {
      reader.close();
    }

    @Override
    public CacheHelper getReaderCacheHelper() {
      return null;
    }
  };
}
 

@SuppressWarnings("unchecked")
private static boolean isFiltered(int notAdjustedDocId, IndexReader reader, Filter filter) throws IOException {
  if (filter == null) {
    return false;
  }
  if (reader instanceof BaseCompositeReader) {
    BaseCompositeReader<IndexReader> indexReader = (BaseCompositeReader<IndexReader>) reader;
    List<? extends IndexReader> sequentialSubReaders = BaseCompositeReaderUtil.getSequentialSubReaders(indexReader);
    int readerIndex = BaseCompositeReaderUtil.readerIndex(indexReader, notAdjustedDocId);
    int readerBase = BaseCompositeReaderUtil.readerBase(indexReader, readerIndex);
    int docId = notAdjustedDocId - readerBase;
    IndexReader orgReader = sequentialSubReaders.get(readerIndex);
    SegmentReader sReader = AtomicReaderUtil.getSegmentReader(orgReader);
    if (sReader != null) {
      SegmentReader segmentReader = (SegmentReader) sReader;
      DocIdSet docIdSet = filter.getDocIdSet(segmentReader.getContext(), segmentReader.getLiveDocs());
      DocIdSetIterator iterator = docIdSet.iterator();
      if (iterator == null) {
        return true;
      }
      if (iterator.advance(docId) == docId) {
        return false;
      }
      return true;
    }
    throw new RuntimeException("Reader has to be a SegmentReader [" + orgReader + "]");
  } else {
    throw new RuntimeException("Reader has to be a BaseCompositeReader [" + reader + "]");
  }
}