diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/plans/logical/object.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/plans/logical/object.scala
index 6225b3fa42..bfb70c2ef4 100644
--- a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/plans/logical/object.scala
+++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/plans/logical/object.scala
@@ -41,7 +41,10 @@ object CatalystSerde {
   }
 
   def generateObjAttr[T : Encoder]: Attribute = {
-    AttributeReference("obj", encoderFor[T].deserializer.dataType, nullable = false)()
+    val enc = encoderFor[T]
+    val dataType = enc.deserializer.dataType
+    val nullable = !enc.clsTag.runtimeClass.isPrimitive
+    AttributeReference("obj", dataType, nullable)()
   }
 }
 
diff --git a/sql/core/src/test/scala/org/apache/spark/sql/DataFrameImplicitsSuite.scala b/sql/core/src/test/scala/org/apache/spark/sql/DataFrameImplicitsSuite.scala
index 094efbaead..63094d1b61 100644
--- a/sql/core/src/test/scala/org/apache/spark/sql/DataFrameImplicitsSuite.scala
+++ b/sql/core/src/test/scala/org/apache/spark/sql/DataFrameImplicitsSuite.scala
@@ -51,4 +51,15 @@ class DataFrameImplicitsSuite extends QueryTest with SharedSQLContext {
       sparkContext.parallelize(1 to 10).map(_.toString).toDF("stringCol"),
       (1 to 10).map(i => Row(i.toString)))
   }
+
+  test("SPARK-19959: df[java.lang.Long].collect includes null throws NullPointerException") {
+    checkAnswer(sparkContext.parallelize(Seq[java.lang.Integer](0, null, 2), 1).toDF,
+      Seq(Row(0), Row(null), Row(2)))
+    checkAnswer(sparkContext.parallelize(Seq[java.lang.Long](0L, null, 2L), 1).toDF,
+      Seq(Row(0L), Row(null), Row(2L)))
+    checkAnswer(sparkContext.parallelize(Seq[java.lang.Float](0.0F, null, 2.0F), 1).toDF,
+      Seq(Row(0.0F), Row(null), Row(2.0F)))
+    checkAnswer(sparkContext.parallelize(Seq[java.lang.Double](0.0D, null, 2.0D), 1).toDF,
+      Seq(Row(0.0D), Row(null), Row(2.0D)))
+  }
 }