diff --git a/core/src/main/scala/org/apache/spark/api/java/JavaRDDLike.scala b/core/src/main/scala/org/apache/spark/api/java/JavaRDDLike.scala
index 8f052fe668ffe..e8124d225fedd 100644
--- a/core/src/main/scala/org/apache/spark/api/java/JavaRDDLike.scala
+++ b/core/src/main/scala/org/apache/spark/api/java/JavaRDDLike.scala
@@ -459,8 +459,8 @@ trait JavaRDDLike[T, This <: JavaRDDLike[T, This]] extends Serializable {
   /**
    * Creates tuples of the elements in this RDD by applying `f`.
    */
-  def keyBy[K](f: JFunction[T, K]): JavaPairRDD[K, T] = {
-    implicit val ctag: ClassTag[K] = fakeClassTag
+  def keyBy[U](f: JFunction[T, U]): JavaPairRDD[U, T] = {
+    implicit val ctag: ClassTag[U] = fakeClassTag
     JavaPairRDD.fromRDD(rdd.keyBy(f))
   }