code: public static void collectCollection(IndexReader reader,
        List<Integer> fullDocSet, ComponentCollection collectionInfo)
        throws IOException {
      if (collectionInfo != null) {
        CodecCollector.collectCollection(reader, fullDocSet, collectionInfo);
      }
    }
docs: Collect collection.
  
  @param reader
  the reader
  @param fullDocSet
  the full doc set
  @param collectionInfo
  the collection info
  @throws IOException
  Signals that an I/O exception has occurred.