How to forecast problem in spark arima

[jinxi...@gmail.com]

Hi，
I have got TimeSeriesRDD in spark, but I don't know how to get the forecast.

val rdd = sc.textFile(path).map { line =>
val tokens = line.split(",")
val series = new DenseVector(tokens.tail.map(_.toDouble))
(tokens.head, series.asInstanceOf[Vector])
}

val start = ZonedDateTime.of(2015, 4, 9, 0, 0, 0, 0, ZoneId.of("Z"))
val index = uniform(start, 250, new DayFrequency(1))
val tsRDD = new TimeSeriesRDD(index, rdd);
val arimaModel = tsRDD.map(tuple => (tuple._1, ARIMA.fitModel(1,0,1,tuple._2)))

Thanks