@Override
    public boolean apply(Writer writer, CacheWriter cacheWriter) throws IOException {
      // LlapIoImpl.LOG.debug("Writing batch " + batch);
      writer.addRowBatch(batch);
      for (ColumnVector cv : batch.cols) {
        if (cv != null) {
          assert (cv.decRef() == 0);
        }
      }
      return false;
    }
The class that writes rows from a text reader to an ORC writer using VectorDeserializeRow.
llap-server/src/java/org/apache/hadoop/hive/llap/io/encoded/VectorDeserializeOrcWriter.java