1 files changed, 5 insertions, 5 deletions
diff --git a/streaming/src/main/scala/org/apache/spark/streaming/dstream/InputDStream.scala b/streaming/src/main/scala/org/apache/spark/streaming/dstream/InputDStream.scala
index 0b6b191dbe..a3c125c306 100644
--- a/streaming/src/main/scala/org/apache/spark/streaming/dstream/InputDStream.scala
+++ b/streaming/src/main/scala/org/apache/spark/streaming/dstream/InputDStream.scala
@@ -39,7 +39,7 @@ import org.apache.spark.util.Utils
  *
  * @param _ssc Streaming context that will execute this input stream
  */
-abstract class InputDStream[T: ClassTag] (_ssc: StreamingContext)
+abstract class InputDStream[T: ClassTag](_ssc: StreamingContext)
   extends DStream[T](_ssc) {
 
   private[streaming] var lastValidTime: Time = null
@@ -90,8 +90,8 @@ abstract class InputDStream[T: ClassTag] (_ssc: StreamingContext)
     } else {
       // Time is valid, but check it it is more than lastValidTime
       if (lastValidTime != null && time < lastValidTime) {
-        logWarning("isTimeValid called with " + time + " where as last valid time is " +
-          lastValidTime)
+        logWarning(s"isTimeValid called with $time whereas the last valid time " +
+          s"is $lastValidTime")
       }
       lastValidTime = time
       true
@@ -107,8 +107,8 @@ abstract class InputDStream[T: ClassTag] (_ssc: StreamingContext)
   }
 
   /** Method called to start receiving data. Subclasses must implement this method. */
-  def start()
+  def start(): Unit
 
   /** Method called to stop receiving data. Subclasses must implement this method. */
-  def stop()
+  def stop(): Unit
 }