build.sbt

scalaVersion := "2.11.7"

libraryDependencies ++= Seq(
  "org.apache.spark" %% "spark-core" % "1.6.1",
  "org.apache.spark" %% "spark-sql" % "1.6.1"
)

puzzle.scala

import org.apache.spark._
import org.apache.spark.sql._
import scala.util.Try

case class Dummy()

object App {
  def main(args: Array[String]) {
    val sc = new SparkContext("local", "foo", new SparkConf())
    val sqlContext = new SQLContext(sc)
    val df = sqlContext.read.json(sc.parallelize(Seq("""{"a": [1, 2, 3]}""")))
    val optionA = Option(df.first.getAs[Dummy]("a")) // No exception
    require(Try(optionA.map(identity)).isFailure) 
    sc.stop()
  }
}