[SPARK-16664][SQL] Fix persist call on Data frames with more than 200…

## What changes were proposed in this pull request?

f12f11e578 introduced this bug, missed foreach as map

## How was this patch tested?

Test added

Author: Wesley Tang <tangmingjun@mininglamp.com>

Closes #14324 from breakdawn/master.

sql/core/src/main/scala/org/apache/spark/sql/execution/columnar/GenerateColumnAccessor.scala

@@ -127,7 +127,7 @@ object GenerateColumnAccessor extends CodeGenerator[Seq[DataType], ColumnarItera
         val groupedAccessorsItr = initializeAccessors.grouped(numberOfStatementsThreshold)
         val groupedExtractorsItr = extractors.grouped(numberOfStatementsThreshold)
         var groupedAccessorsLength = 0
-        groupedAccessorsItr.zipWithIndex.map { case (body, i) =>
+        groupedAccessorsItr.zipWithIndex.foreach { case (body, i) =>
           groupedAccessorsLength += 1
           val funcName = s"accessors$i"
           val funcCode = s"""
@@ -137,7 +137,7 @@ object GenerateColumnAccessor extends CodeGenerator[Seq[DataType], ColumnarItera
            """.stripMargin
           ctx.addNewFunction(funcName, funcCode)
         }
-        groupedExtractorsItr.zipWithIndex.map { case (body, i) =>
+        groupedExtractorsItr.zipWithIndex.foreach { case (body, i) =>
           val funcName = s"extractors$i"
           val funcCode = s"""
              |private void $funcName() {

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

@@ -1571,4 +1571,12 @@ class DataFrameSuite extends QueryTest with SharedSQLContext {
     checkAnswer(joined, Row("x", null, null))
     checkAnswer(joined.filter($"new".isNull), Row("x", null, null))
   }
+
+  test("SPARK-16664: persist with more than 200 columns") {
+    val size = 201L
+    val rdd = sparkContext.makeRDD(Seq(Row.fromSeq(Seq.range(0, size))))
+    val schemas = List.range(0, size).map(a => StructField("name" + a, LongType, true))
+    val df = spark.createDataFrame(rdd, StructType(schemas), false)
+    assert(df.persist.take(1).apply(0).toSeq(100).asInstanceOf[Long] == 100)
+  }
 }

sql/core/src/test/scala/org/apache/spark/sql/execution/columnar/InMemoryColumnarQuerySuite.scala

@@ -227,7 +227,8 @@ class InMemoryColumnarQuerySuite extends QueryTest with SharedSQLContext {
     val columnTypes1 = List.fill(length1)(IntegerType)
     val columnarIterator1 = GenerateColumnAccessor.generate(columnTypes1)
 
-    val length2 = 10000
+    // SPARK-16664: the limit of janino is 8117
+    val length2 = 8117
     val columnTypes2 = List.fill(length2)(IntegerType)
     val columnarIterator2 = GenerateColumnAccessor.generate(columnTypes2)
   }