private void cleanUpCurrentRead() {
    if (currentFileRead == null) return;
    try {
      currentFileRead.closeOffsetReader();
      currentFileRead = null;
    } catch (Exception ex) {
      LlapIoImpl.LOG.error("Failed to close current file reader", ex);
    }
  }
This class only exists because Java doesn't have yield return. The original method
before this change only needed yield return-s sprinkled here and there; however,
Java developers are usually paid by class, so here we go.
llap-server/src/java/org/apache/hadoop/hive/llap/io/encoded/SerDeEncodedDataReader.java