[SQL] Convert arguments to Scala UDFs

Author: Michael Armbrust <michael@databricks.com>

Closes #3077 from marmbrus/udfsWithUdts and squashes the following commits:

34b5f27 [Michael Armbrust] style
504adef [Michael Armbrust] Convert arguments to Scala UDFs

sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/ScalaUdf.scala

@@ -34,320 +34,366 @@ case class ScalaUdf(function: AnyRef, dataType: DataType, children: Seq[Expressi
 
   override def toString = s"scalaUDF(${children.mkString(",")})"
 
+  // scalastyle:off
+
   /** This method has been generated by this script
 
     (1 to 22).map { x =>
       val anys = (1 to x).map(x => "Any").reduce(_ + ", " + _)
-      val evals = (0 to x - 1).map(x => s"children($x).eval(input)").reduce(_ + ",\n    " + _)
+      val evals = (0 to x - 1).map(x => s"    ScalaReflection.convertToScala(children($x).eval(input), children($x).dataType)").reduce(_ + ",\n    " + _)
 
     s"""
     case $x =>
       function.asInstanceOf[($anys) => Any](
-      $evals)
+    $evals)
     """
-    }
+    }.foreach(println)
 
   */
 
-  // scalastyle:off
   override def eval(input: Row): Any = {
     val result = children.size match {
       case 0 => function.asInstanceOf[() => Any]()
-      case 1 => function.asInstanceOf[(Any) => Any](children(0).eval(input))
+      case 1 =>
+        function.asInstanceOf[(Any) => Any](
+          ScalaReflection.convertToScala(children(0).eval(input), children(0).dataType))
+
+
       case 2 =>
         function.asInstanceOf[(Any, Any) => Any](
-          children(0).eval(input),
-          children(1).eval(input))
+          ScalaReflection.convertToScala(children(0).eval(input), children(0).dataType),
+          ScalaReflection.convertToScala(children(1).eval(input), children(1).dataType))
+
+
       case 3 =>
         function.asInstanceOf[(Any, Any, Any) => Any](
-          children(0).eval(input),
-          children(1).eval(input),
-          children(2).eval(input))
+          ScalaReflection.convertToScala(children(0).eval(input), children(0).dataType),
+          ScalaReflection.convertToScala(children(1).eval(input), children(1).dataType),
+          ScalaReflection.convertToScala(children(2).eval(input), children(2).dataType))
+
+
       case 4 =>
         function.asInstanceOf[(Any, Any, Any, Any) => Any](
-          children(0).eval(input),
-          children(1).eval(input),
-          children(2).eval(input),
-          children(3).eval(input))
+          ScalaReflection.convertToScala(children(0).eval(input), children(0).dataType),
+          ScalaReflection.convertToScala(children(1).eval(input), children(1).dataType),
+          ScalaReflection.convertToScala(children(2).eval(input), children(2).dataType),
+          ScalaReflection.convertToScala(children(3).eval(input), children(3).dataType))
+
+
       case 5 =>
         function.asInstanceOf[(Any, Any, Any, Any, Any) => Any](
-          children(0).eval(input),
-          children(1).eval(input),
-          children(2).eval(input),
-          children(3).eval(input),
-          children(4).eval(input))
+          ScalaReflection.convertToScala(children(0).eval(input), children(0).dataType),
+          ScalaReflection.convertToScala(children(1).eval(input), children(1).dataType),
+          ScalaReflection.convertToScala(children(2).eval(input), children(2).dataType),
+          ScalaReflection.convertToScala(children(3).eval(input), children(3).dataType),
+          ScalaReflection.convertToScala(children(4).eval(input), children(4).dataType))
+
+
       case 6 =>
         function.asInstanceOf[(Any, Any, Any, Any, Any, Any) => Any](
-          children(0).eval(input),
-          children(1).eval(input),
-          children(2).eval(input),
-          children(3).eval(input),
-          children(4).eval(input),
-          children(5).eval(input))
+          ScalaReflection.convertToScala(children(0).eval(input), children(0).dataType),
+          ScalaReflection.convertToScala(children(1).eval(input), children(1).dataType),
+          ScalaReflection.convertToScala(children(2).eval(input), children(2).dataType),
+          ScalaReflection.convertToScala(children(3).eval(input), children(3).dataType),
+          ScalaReflection.convertToScala(children(4).eval(input), children(4).dataType),
+          ScalaReflection.convertToScala(children(5).eval(input), children(5).dataType))
+
+
       case 7 =>
         function.asInstanceOf[(Any, Any, Any, Any, Any, Any, Any) => Any](
-          children(0).eval(input),
-          children(1).eval(input),
-          children(2).eval(input),
-          children(3).eval(input),
-          children(4).eval(input),
-          children(5).eval(input),
-          children(6).eval(input))
+          ScalaReflection.convertToScala(children(0).eval(input), children(0).dataType),
+          ScalaReflection.convertToScala(children(1).eval(input), children(1).dataType),
+          ScalaReflection.convertToScala(children(2).eval(input), children(2).dataType),
+          ScalaReflection.convertToScala(children(3).eval(input), children(3).dataType),
+          ScalaReflection.convertToScala(children(4).eval(input), children(4).dataType),
+          ScalaReflection.convertToScala(children(5).eval(input), children(5).dataType),
+          ScalaReflection.convertToScala(children(6).eval(input), children(6).dataType))
+
+
       case 8 =>
         function.asInstanceOf[(Any, Any, Any, Any, Any, Any, Any, Any) => Any](
-          children(0).eval(input),
-          children(1).eval(input),
-          children(2).eval(input),
-          children(3).eval(input),
-          children(4).eval(input),
-          children(5).eval(input),
-          children(6).eval(input),
-          children(7).eval(input))
+          ScalaReflection.convertToScala(children(0).eval(input), children(0).dataType),
+          ScalaReflection.convertToScala(children(1).eval(input), children(1).dataType),
+          ScalaReflection.convertToScala(children(2).eval(input), children(2).dataType),
+          ScalaReflection.convertToScala(children(3).eval(input), children(3).dataType),
+          ScalaReflection.convertToScala(children(4).eval(input), children(4).dataType),
+          ScalaReflection.convertToScala(children(5).eval(input), children(5).dataType),
+          ScalaReflection.convertToScala(children(6).eval(input), children(6).dataType),
+          ScalaReflection.convertToScala(children(7).eval(input), children(7).dataType))
+
+
       case 9 =>
         function.asInstanceOf[(Any, Any, Any, Any, Any, Any, Any, Any, Any) => Any](
-          children(0).eval(input),
-          children(1).eval(input),
-          children(2).eval(input),
-          children(3).eval(input),
-          children(4).eval(input),
-          children(5).eval(input),
-          children(6).eval(input),
-          children(7).eval(input),
-          children(8).eval(input))
+          ScalaReflection.convertToScala(children(0).eval(input), children(0).dataType),
+          ScalaReflection.convertToScala(children(1).eval(input), children(1).dataType),
+          ScalaReflection.convertToScala(children(2).eval(input), children(2).dataType),
+          ScalaReflection.convertToScala(children(3).eval(input), children(3).dataType),
+          ScalaReflection.convertToScala(children(4).eval(input), children(4).dataType),
+          ScalaReflection.convertToScala(children(5).eval(input), children(5).dataType),
+          ScalaReflection.convertToScala(children(6).eval(input), children(6).dataType),
+          ScalaReflection.convertToScala(children(7).eval(input), children(7).dataType),
+          ScalaReflection.convertToScala(children(8).eval(input), children(8).dataType))
+
+
       case 10 =>
         function.asInstanceOf[(Any, Any, Any, Any, Any, Any, Any, Any, Any, Any) => Any](
-          children(0).eval(input),
-          children(1).eval(input),
-          children(2).eval(input),
-          children(3).eval(input),
-          children(4).eval(input),
-          children(5).eval(input),
-          children(6).eval(input),
-          children(7).eval(input),
-          children(8).eval(input),
-          children(9).eval(input))
+          ScalaReflection.convertToScala(children(0).eval(input), children(0).dataType),
+          ScalaReflection.convertToScala(children(1).eval(input), children(1).dataType),
+          ScalaReflection.convertToScala(children(2).eval(input), children(2).dataType),
+          ScalaReflection.convertToScala(children(3).eval(input), children(3).dataType),
+          ScalaReflection.convertToScala(children(4).eval(input), children(4).dataType),
+          ScalaReflection.convertToScala(children(5).eval(input), children(5).dataType),
+          ScalaReflection.convertToScala(children(6).eval(input), children(6).dataType),
+          ScalaReflection.convertToScala(children(7).eval(input), children(7).dataType),
+          ScalaReflection.convertToScala(children(8).eval(input), children(8).dataType),
+          ScalaReflection.convertToScala(children(9).eval(input), children(9).dataType))
+
+
       case 11 =>
         function.asInstanceOf[(Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any) => Any](
-          children(0).eval(input),
-          children(1).eval(input),
-          children(2).eval(input),
-          children(3).eval(input),
-          children(4).eval(input),
-          children(5).eval(input),
-          children(6).eval(input),
-          children(7).eval(input),
-          children(8).eval(input),
-          children(9).eval(input),
-          children(10).eval(input))
+          ScalaReflection.convertToScala(children(0).eval(input), children(0).dataType),
+          ScalaReflection.convertToScala(children(1).eval(input), children(1).dataType),
+          ScalaReflection.convertToScala(children(2).eval(input), children(2).dataType),
+          ScalaReflection.convertToScala(children(3).eval(input), children(3).dataType),
+          ScalaReflection.convertToScala(children(4).eval(input), children(4).dataType),
+          ScalaReflection.convertToScala(children(5).eval(input), children(5).dataType),
+          ScalaReflection.convertToScala(children(6).eval(input), children(6).dataType),
+          ScalaReflection.convertToScala(children(7).eval(input), children(7).dataType),
+          ScalaReflection.convertToScala(children(8).eval(input), children(8).dataType),
+          ScalaReflection.convertToScala(children(9).eval(input), children(9).dataType),
+          ScalaReflection.convertToScala(children(10).eval(input), children(10).dataType))
+
+
       case 12 =>
         function.asInstanceOf[(Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any) => Any](
-          children(0).eval(input),
-          children(1).eval(input),
-          children(2).eval(input),
-          children(3).eval(input),
-          children(4).eval(input),
-          children(5).eval(input),
-          children(6).eval(input),
-          children(7).eval(input),
-          children(8).eval(input),
-          children(9).eval(input),
-          children(10).eval(input),
-          children(11).eval(input))
+          ScalaReflection.convertToScala(children(0).eval(input), children(0).dataType),
+          ScalaReflection.convertToScala(children(1).eval(input), children(1).dataType),
+          ScalaReflection.convertToScala(children(2).eval(input), children(2).dataType),
+          ScalaReflection.convertToScala(children(3).eval(input), children(3).dataType),
+          ScalaReflection.convertToScala(children(4).eval(input), children(4).dataType),
+          ScalaReflection.convertToScala(children(5).eval(input), children(5).dataType),
+          ScalaReflection.convertToScala(children(6).eval(input), children(6).dataType),
+          ScalaReflection.convertToScala(children(7).eval(input), children(7).dataType),
+          ScalaReflection.convertToScala(children(8).eval(input), children(8).dataType),
+          ScalaReflection.convertToScala(children(9).eval(input), children(9).dataType),
+          ScalaReflection.convertToScala(children(10).eval(input), children(10).dataType),
+          ScalaReflection.convertToScala(children(11).eval(input), children(11).dataType))
+
+
       case 13 =>
         function.asInstanceOf[(Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any) => Any](
-          children(0).eval(input),
-          children(1).eval(input),
-          children(2).eval(input),
-          children(3).eval(input),
-          children(4).eval(input),
-          children(5).eval(input),
-          children(6).eval(input),
-          children(7).eval(input),
-          children(8).eval(input),
-          children(9).eval(input),
-          children(10).eval(input),
-          children(11).eval(input),
-          children(12).eval(input))
+          ScalaReflection.convertToScala(children(0).eval(input), children(0).dataType),
+          ScalaReflection.convertToScala(children(1).eval(input), children(1).dataType),
+          ScalaReflection.convertToScala(children(2).eval(input), children(2).dataType),
+          ScalaReflection.convertToScala(children(3).eval(input), children(3).dataType),
+          ScalaReflection.convertToScala(children(4).eval(input), children(4).dataType),
+          ScalaReflection.convertToScala(children(5).eval(input), children(5).dataType),
+          ScalaReflection.convertToScala(children(6).eval(input), children(6).dataType),
+          ScalaReflection.convertToScala(children(7).eval(input), children(7).dataType),
+          ScalaReflection.convertToScala(children(8).eval(input), children(8).dataType),
+          ScalaReflection.convertToScala(children(9).eval(input), children(9).dataType),
+          ScalaReflection.convertToScala(children(10).eval(input), children(10).dataType),
+          ScalaReflection.convertToScala(children(11).eval(input), children(11).dataType),
+          ScalaReflection.convertToScala(children(12).eval(input), children(12).dataType))
+
+
       case 14 =>
         function.asInstanceOf[(Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any) => Any](
-          children(0).eval(input),
-          children(1).eval(input),
-          children(2).eval(input),
-          children(3).eval(input),
-          children(4).eval(input),
-          children(5).eval(input),
-          children(6).eval(input),
-          children(7).eval(input),
-          children(8).eval(input),
-          children(9).eval(input),
-          children(10).eval(input),
-          children(11).eval(input),
-          children(12).eval(input),
-          children(13).eval(input))
+          ScalaReflection.convertToScala(children(0).eval(input), children(0).dataType),
+          ScalaReflection.convertToScala(children(1).eval(input), children(1).dataType),
+          ScalaReflection.convertToScala(children(2).eval(input), children(2).dataType),
+          ScalaReflection.convertToScala(children(3).eval(input), children(3).dataType),
+          ScalaReflection.convertToScala(children(4).eval(input), children(4).dataType),
+          ScalaReflection.convertToScala(children(5).eval(input), children(5).dataType),
+          ScalaReflection.convertToScala(children(6).eval(input), children(6).dataType),
+          ScalaReflection.convertToScala(children(7).eval(input), children(7).dataType),
+          ScalaReflection.convertToScala(children(8).eval(input), children(8).dataType),
+          ScalaReflection.convertToScala(children(9).eval(input), children(9).dataType),
+          ScalaReflection.convertToScala(children(10).eval(input), children(10).dataType),
+          ScalaReflection.convertToScala(children(11).eval(input), children(11).dataType),
+          ScalaReflection.convertToScala(children(12).eval(input), children(12).dataType),
+          ScalaReflection.convertToScala(children(13).eval(input), children(13).dataType))
+
+
       case 15 =>
         function.asInstanceOf[(Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any) => Any](
-          children(0).eval(input),
-          children(1).eval(input),
-          children(2).eval(input),
-          children(3).eval(input),
-          children(4).eval(input),
-          children(5).eval(input),
-          children(6).eval(input),
-          children(7).eval(input),
-          children(8).eval(input),
-          children(9).eval(input),
-          children(10).eval(input),
-          children(11).eval(input),
-          children(12).eval(input),
-          children(13).eval(input),
-          children(14).eval(input))
+          ScalaReflection.convertToScala(children(0).eval(input), children(0).dataType),
+          ScalaReflection.convertToScala(children(1).eval(input), children(1).dataType),
+          ScalaReflection.convertToScala(children(2).eval(input), children(2).dataType),
+          ScalaReflection.convertToScala(children(3).eval(input), children(3).dataType),
+          ScalaReflection.convertToScala(children(4).eval(input), children(4).dataType),
+          ScalaReflection.convertToScala(children(5).eval(input), children(5).dataType),
+          ScalaReflection.convertToScala(children(6).eval(input), children(6).dataType),
+          ScalaReflection.convertToScala(children(7).eval(input), children(7).dataType),
+          ScalaReflection.convertToScala(children(8).eval(input), children(8).dataType),
+          ScalaReflection.convertToScala(children(9).eval(input), children(9).dataType),
+          ScalaReflection.convertToScala(children(10).eval(input), children(10).dataType),
+          ScalaReflection.convertToScala(children(11).eval(input), children(11).dataType),
+          ScalaReflection.convertToScala(children(12).eval(input), children(12).dataType),
+          ScalaReflection.convertToScala(children(13).eval(input), children(13).dataType),
+          ScalaReflection.convertToScala(children(14).eval(input), children(14).dataType))
+
+
       case 16 =>
         function.asInstanceOf[(Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any) => Any](
-          children(0).eval(input),
-          children(1).eval(input),
-          children(2).eval(input),
-          children(3).eval(input),
-          children(4).eval(input),
-          children(5).eval(input),
-          children(6).eval(input),
-          children(7).eval(input),
-          children(8).eval(input),
-          children(9).eval(input),
-          children(10).eval(input),
-          children(11).eval(input),
-          children(12).eval(input),
-          children(13).eval(input),
-          children(14).eval(input),
-          children(15).eval(input))
+          ScalaReflection.convertToScala(children(0).eval(input), children(0).dataType),
+          ScalaReflection.convertToScala(children(1).eval(input), children(1).dataType),
+          ScalaReflection.convertToScala(children(2).eval(input), children(2).dataType),
+          ScalaReflection.convertToScala(children(3).eval(input), children(3).dataType),
+          ScalaReflection.convertToScala(children(4).eval(input), children(4).dataType),
+          ScalaReflection.convertToScala(children(5).eval(input), children(5).dataType),
+          ScalaReflection.convertToScala(children(6).eval(input), children(6).dataType),
+          ScalaReflection.convertToScala(children(7).eval(input), children(7).dataType),
+          ScalaReflection.convertToScala(children(8).eval(input), children(8).dataType),
+          ScalaReflection.convertToScala(children(9).eval(input), children(9).dataType),
+          ScalaReflection.convertToScala(children(10).eval(input), children(10).dataType),
+          ScalaReflection.convertToScala(children(11).eval(input), children(11).dataType),
+          ScalaReflection.convertToScala(children(12).eval(input), children(12).dataType),
+          ScalaReflection.convertToScala(children(13).eval(input), children(13).dataType),
+          ScalaReflection.convertToScala(children(14).eval(input), children(14).dataType),
+          ScalaReflection.convertToScala(children(15).eval(input), children(15).dataType))
+
+
       case 17 =>
         function.asInstanceOf[(Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any) => Any](
-          children(0).eval(input),
-          children(1).eval(input),
-          children(2).eval(input),
-          children(3).eval(input),
-          children(4).eval(input),
-          children(5).eval(input),
-          children(6).eval(input),
-          children(7).eval(input),
-          children(8).eval(input),
-          children(9).eval(input),
-          children(10).eval(input),
-          children(11).eval(input),
-          children(12).eval(input),
-          children(13).eval(input),
-          children(14).eval(input),
-          children(15).eval(input),
-          children(16).eval(input))
+          ScalaReflection.convertToScala(children(0).eval(input), children(0).dataType),
+          ScalaReflection.convertToScala(children(1).eval(input), children(1).dataType),
+          ScalaReflection.convertToScala(children(2).eval(input), children(2).dataType),
+          ScalaReflection.convertToScala(children(3).eval(input), children(3).dataType),
+          ScalaReflection.convertToScala(children(4).eval(input), children(4).dataType),
+          ScalaReflection.convertToScala(children(5).eval(input), children(5).dataType),
+          ScalaReflection.convertToScala(children(6).eval(input), children(6).dataType),
+          ScalaReflection.convertToScala(children(7).eval(input), children(7).dataType),
+          ScalaReflection.convertToScala(children(8).eval(input), children(8).dataType),
+          ScalaReflection.convertToScala(children(9).eval(input), children(9).dataType),
+          ScalaReflection.convertToScala(children(10).eval(input), children(10).dataType),
+          ScalaReflection.convertToScala(children(11).eval(input), children(11).dataType),
+          ScalaReflection.convertToScala(children(12).eval(input), children(12).dataType),
+          ScalaReflection.convertToScala(children(13).eval(input), children(13).dataType),
+          ScalaReflection.convertToScala(children(14).eval(input), children(14).dataType),
+          ScalaReflection.convertToScala(children(15).eval(input), children(15).dataType),
+          ScalaReflection.convertToScala(children(16).eval(input), children(16).dataType))
+
+
       case 18 =>
         function.asInstanceOf[(Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any) => Any](
-          children(0).eval(input),
-          children(1).eval(input),
-          children(2).eval(input),
-          children(3).eval(input),
-          children(4).eval(input),
-          children(5).eval(input),
-          children(6).eval(input),
-          children(7).eval(input),
-          children(8).eval(input),
-          children(9).eval(input),
-          children(10).eval(input),
-          children(11).eval(input),
-          children(12).eval(input),
-          children(13).eval(input),
-          children(14).eval(input),
-          children(15).eval(input),
-          children(16).eval(input),
-          children(17).eval(input))
+          ScalaReflection.convertToScala(children(0).eval(input), children(0).dataType),
+          ScalaReflection.convertToScala(children(1).eval(input), children(1).dataType),
+          ScalaReflection.convertToScala(children(2).eval(input), children(2).dataType),
+          ScalaReflection.convertToScala(children(3).eval(input), children(3).dataType),
+          ScalaReflection.convertToScala(children(4).eval(input), children(4).dataType),
+          ScalaReflection.convertToScala(children(5).eval(input), children(5).dataType),
+          ScalaReflection.convertToScala(children(6).eval(input), children(6).dataType),
+          ScalaReflection.convertToScala(children(7).eval(input), children(7).dataType),
+          ScalaReflection.convertToScala(children(8).eval(input), children(8).dataType),
+          ScalaReflection.convertToScala(children(9).eval(input), children(9).dataType),
+          ScalaReflection.convertToScala(children(10).eval(input), children(10).dataType),
+          ScalaReflection.convertToScala(children(11).eval(input), children(11).dataType),
+          ScalaReflection.convertToScala(children(12).eval(input), children(12).dataType),
+          ScalaReflection.convertToScala(children(13).eval(input), children(13).dataType),
+          ScalaReflection.convertToScala(children(14).eval(input), children(14).dataType),
+          ScalaReflection.convertToScala(children(15).eval(input), children(15).dataType),
+          ScalaReflection.convertToScala(children(16).eval(input), children(16).dataType),
+          ScalaReflection.convertToScala(children(17).eval(input), children(17).dataType))
+
+
       case 19 =>
         function.asInstanceOf[(Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any) => Any](
-          children(0).eval(input),
-          children(1).eval(input),
-          children(2).eval(input),
-          children(3).eval(input),
-          children(4).eval(input),
-          children(5).eval(input),
-          children(6).eval(input),
-          children(7).eval(input),
-          children(8).eval(input),
-          children(9).eval(input),
-          children(10).eval(input),
-          children(11).eval(input),
-          children(12).eval(input),
-          children(13).eval(input),
-          children(14).eval(input),
-          children(15).eval(input),
-          children(16).eval(input),
-          children(17).eval(input),
-          children(18).eval(input))
+          ScalaReflection.convertToScala(children(0).eval(input), children(0).dataType),
+          ScalaReflection.convertToScala(children(1).eval(input), children(1).dataType),
+          ScalaReflection.convertToScala(children(2).eval(input), children(2).dataType),
+          ScalaReflection.convertToScala(children(3).eval(input), children(3).dataType),
+          ScalaReflection.convertToScala(children(4).eval(input), children(4).dataType),
+          ScalaReflection.convertToScala(children(5).eval(input), children(5).dataType),
+          ScalaReflection.convertToScala(children(6).eval(input), children(6).dataType),
+          ScalaReflection.convertToScala(children(7).eval(input), children(7).dataType),
+          ScalaReflection.convertToScala(children(8).eval(input), children(8).dataType),
+          ScalaReflection.convertToScala(children(9).eval(input), children(9).dataType),
+          ScalaReflection.convertToScala(children(10).eval(input), children(10).dataType),
+          ScalaReflection.convertToScala(children(11).eval(input), children(11).dataType),
+          ScalaReflection.convertToScala(children(12).eval(input), children(12).dataType),
+          ScalaReflection.convertToScala(children(13).eval(input), children(13).dataType),
+          ScalaReflection.convertToScala(children(14).eval(input), children(14).dataType),
+          ScalaReflection.convertToScala(children(15).eval(input), children(15).dataType),
+          ScalaReflection.convertToScala(children(16).eval(input), children(16).dataType),
+          ScalaReflection.convertToScala(children(17).eval(input), children(17).dataType),
+          ScalaReflection.convertToScala(children(18).eval(input), children(18).dataType))
+
+
       case 20 =>
         function.asInstanceOf[(Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any) => Any](
-          children(0).eval(input),
-          children(1).eval(input),
-          children(2).eval(input),
-          children(3).eval(input),
-          children(4).eval(input),
-          children(5).eval(input),
-          children(6).eval(input),
-          children(7).eval(input),
-          children(8).eval(input),
-          children(9).eval(input),
-          children(10).eval(input),
-          children(11).eval(input),
-          children(12).eval(input),
-          children(13).eval(input),
-          children(14).eval(input),
-          children(15).eval(input),
-          children(16).eval(input),
-          children(17).eval(input),
-          children(18).eval(input),
-          children(19).eval(input))
+          ScalaReflection.convertToScala(children(0).eval(input), children(0).dataType),
+          ScalaReflection.convertToScala(children(1).eval(input), children(1).dataType),
+          ScalaReflection.convertToScala(children(2).eval(input), children(2).dataType),
+          ScalaReflection.convertToScala(children(3).eval(input), children(3).dataType),
+          ScalaReflection.convertToScala(children(4).eval(input), children(4).dataType),
+          ScalaReflection.convertToScala(children(5).eval(input), children(5).dataType),
+          ScalaReflection.convertToScala(children(6).eval(input), children(6).dataType),
+          ScalaReflection.convertToScala(children(7).eval(input), children(7).dataType),
+          ScalaReflection.convertToScala(children(8).eval(input), children(8).dataType),
+          ScalaReflection.convertToScala(children(9).eval(input), children(9).dataType),
+          ScalaReflection.convertToScala(children(10).eval(input), children(10).dataType),
+          ScalaReflection.convertToScala(children(11).eval(input), children(11).dataType),
+          ScalaReflection.convertToScala(children(12).eval(input), children(12).dataType),
+          ScalaReflection.convertToScala(children(13).eval(input), children(13).dataType),
+          ScalaReflection.convertToScala(children(14).eval(input), children(14).dataType),
+          ScalaReflection.convertToScala(children(15).eval(input), children(15).dataType),
+          ScalaReflection.convertToScala(children(16).eval(input), children(16).dataType),
+          ScalaReflection.convertToScala(children(17).eval(input), children(17).dataType),
+          ScalaReflection.convertToScala(children(18).eval(input), children(18).dataType),
+          ScalaReflection.convertToScala(children(19).eval(input), children(19).dataType))
+
+
       case 21 =>
         function.asInstanceOf[(Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any) => Any](
-          children(0).eval(input),
-          children(1).eval(input),
-          children(2).eval(input),
-          children(3).eval(input),
-          children(4).eval(input),
-          children(5).eval(input),
-          children(6).eval(input),
-          children(7).eval(input),
-          children(8).eval(input),
-          children(9).eval(input),
-          children(10).eval(input),
-          children(11).eval(input),
-          children(12).eval(input),
-          children(13).eval(input),
-          children(14).eval(input),
-          children(15).eval(input),
-          children(16).eval(input),
-          children(17).eval(input),
-          children(18).eval(input),
-          children(19).eval(input),
-          children(20).eval(input))
+          ScalaReflection.convertToScala(children(0).eval(input), children(0).dataType),
+          ScalaReflection.convertToScala(children(1).eval(input), children(1).dataType),
+          ScalaReflection.convertToScala(children(2).eval(input), children(2).dataType),
+          ScalaReflection.convertToScala(children(3).eval(input), children(3).dataType),
+          ScalaReflection.convertToScala(children(4).eval(input), children(4).dataType),
+          ScalaReflection.convertToScala(children(5).eval(input), children(5).dataType),
+          ScalaReflection.convertToScala(children(6).eval(input), children(6).dataType),
+          ScalaReflection.convertToScala(children(7).eval(input), children(7).dataType),
+          ScalaReflection.convertToScala(children(8).eval(input), children(8).dataType),
+          ScalaReflection.convertToScala(children(9).eval(input), children(9).dataType),
+          ScalaReflection.convertToScala(children(10).eval(input), children(10).dataType),
+          ScalaReflection.convertToScala(children(11).eval(input), children(11).dataType),
+          ScalaReflection.convertToScala(children(12).eval(input), children(12).dataType),
+          ScalaReflection.convertToScala(children(13).eval(input), children(13).dataType),
+          ScalaReflection.convertToScala(children(14).eval(input), children(14).dataType),
+          ScalaReflection.convertToScala(children(15).eval(input), children(15).dataType),
+          ScalaReflection.convertToScala(children(16).eval(input), children(16).dataType),
+          ScalaReflection.convertToScala(children(17).eval(input), children(17).dataType),
+          ScalaReflection.convertToScala(children(18).eval(input), children(18).dataType),
+          ScalaReflection.convertToScala(children(19).eval(input), children(19).dataType),
+          ScalaReflection.convertToScala(children(20).eval(input), children(20).dataType))
+
+
       case 22 =>
         function.asInstanceOf[(Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any, Any) => Any](
-          children(0).eval(input),
-          children(1).eval(input),
-          children(2).eval(input),
-          children(3).eval(input),
-          children(4).eval(input),
-          children(5).eval(input),
-          children(6).eval(input),
-          children(7).eval(input),
-          children(8).eval(input),
-          children(9).eval(input),
-          children(10).eval(input),
-          children(11).eval(input),
-          children(12).eval(input),
-          children(13).eval(input),
-          children(14).eval(input),
-          children(15).eval(input),
-          children(16).eval(input),
-          children(17).eval(input),
-          children(18).eval(input),
-          children(19).eval(input),
-          children(20).eval(input),
-          children(21).eval(input))
+          ScalaReflection.convertToScala(children(0).eval(input), children(0).dataType),
+          ScalaReflection.convertToScala(children(1).eval(input), children(1).dataType),
+          ScalaReflection.convertToScala(children(2).eval(input), children(2).dataType),
+          ScalaReflection.convertToScala(children(3).eval(input), children(3).dataType),
+          ScalaReflection.convertToScala(children(4).eval(input), children(4).dataType),
+          ScalaReflection.convertToScala(children(5).eval(input), children(5).dataType),
+          ScalaReflection.convertToScala(children(6).eval(input), children(6).dataType),
+          ScalaReflection.convertToScala(children(7).eval(input), children(7).dataType),
+          ScalaReflection.convertToScala(children(8).eval(input), children(8).dataType),
+          ScalaReflection.convertToScala(children(9).eval(input), children(9).dataType),
+          ScalaReflection.convertToScala(children(10).eval(input), children(10).dataType),
+          ScalaReflection.convertToScala(children(11).eval(input), children(11).dataType),
+          ScalaReflection.convertToScala(children(12).eval(input), children(12).dataType),
+          ScalaReflection.convertToScala(children(13).eval(input), children(13).dataType),
+          ScalaReflection.convertToScala(children(14).eval(input), children(14).dataType),
+          ScalaReflection.convertToScala(children(15).eval(input), children(15).dataType),
+          ScalaReflection.convertToScala(children(16).eval(input), children(16).dataType),
+          ScalaReflection.convertToScala(children(17).eval(input), children(17).dataType),
+          ScalaReflection.convertToScala(children(18).eval(input), children(18).dataType),
+          ScalaReflection.convertToScala(children(19).eval(input), children(19).dataType),
+          ScalaReflection.convertToScala(children(20).eval(input), children(20).dataType),
+          ScalaReflection.convertToScala(children(21).eval(input), children(21).dataType))
+
     }
     // scalastyle:on
 

sql/core/src/test/scala/org/apache/spark/sql/UserDefinedTypeSuite.scala

@@ -60,13 +60,13 @@ private[sql] class MyDenseVectorUDT extends UserDefinedType[MyDenseVector] {
 }
 
 class UserDefinedTypeSuite extends QueryTest {
+  val points = Seq(
+    MyLabeledPoint(1.0, new MyDenseVector(Array(0.1, 1.0))),
+    MyLabeledPoint(0.0, new MyDenseVector(Array(0.2, 2.0))))
+  val pointsRDD: RDD[MyLabeledPoint] = sparkContext.parallelize(points)
 
-  test("register user type: MyDenseVector for MyLabeledPoint") {
-    val points = Seq(
-      MyLabeledPoint(1.0, new MyDenseVector(Array(0.1, 1.0))),
-      MyLabeledPoint(0.0, new MyDenseVector(Array(0.2, 2.0))))
-    val pointsRDD: RDD[MyLabeledPoint] = sparkContext.parallelize(points)
 
+  test("register user type: MyDenseVector for MyLabeledPoint") {
     val labels: RDD[Double] = pointsRDD.select('label).map { case Row(v: Double) => v }
     val labelsArrays: Array[Double] = labels.collect()
     assert(labelsArrays.size === 2)
@@ -80,4 +80,12 @@ class UserDefinedTypeSuite extends QueryTest {
     assert(featuresArrays.contains(new MyDenseVector(Array(0.1, 1.0))))
     assert(featuresArrays.contains(new MyDenseVector(Array(0.2, 2.0))))
   }
+
+  test("UDTs and UDFs") {
+    registerFunction("testType", (d: MyDenseVector) => d.isInstanceOf[MyDenseVector])
+    pointsRDD.registerTempTable("points")
+    checkAnswer(
+      sql("SELECT testType(features) from points"),
+      Seq(Row(true), Row(true)))
+  }
 }