code: public static JavaRDD<MultiDataSet> mapRRMDSI(JavaRDD<List<Writable>> rdd, RecordReaderMultiDataSetIterator iterator){
          checkIterator(iterator, 1, 0);
          return mapRRMDSIRecords(rdd.map(new Function<List<Writable>,DataVecRecords>(){
              @Override
              public DataVecRecords call(List<Writable> v1) throws Exception {
                  return new DataVecRecords(Collections.singletonList(v1), null);
              }
          }), iterator);
      }
docs: Apply a single reader {@link RecordReaderMultiDataSetIterator} to a {@code JavaRDD<List<Writable>>}.
  <b>NOTE</b>: The RecordReaderMultiDataSetIterator <it>must</it> use {@link SparkSourceDummyReader} in place of
  "real" RecordReader instances
  
  @param rdd      RDD with writables
  @param iterator RecordReaderMultiDataSetIterator with {@link SparkSourceDummyReader} readers