add arraylist to dataframe

[KhajaAsmath Mohammed]

Hi,

I am initiating arraylist before iterating throuugh the map method. I am
always getting the list size value as zero after map operation.

How do I add values to list inside the map method of dataframe ? any
suggestions?

 val points = new
java.util.ArrayList[com.vividsolutions.jts.geom.Coordinate]()
    import scala.collection.JavaConversions._
    df.rdd.map { row =>
        val latitude =
com.navistar.telematics.datascience.validation.PreValidation.getDefaultDoubleVal(row.getAs[String](Constants.Datapoint.Latitude))
        val longitude =
com.navistar.telematics.datascience.validation.PreValidation.getDefaultDoubleVal(row.getAs[String](Constants.Datapoint.Longitude))
        points.add(new Coordinate(latitude, longitude))

    }
points.size is always zero.


Thanks,
Asmath