[MINOR][DOCS] Use multi-line JavaDoc comments in Scala code.

## What changes were proposed in this pull request?

This PR aims to fix all Scala-Style multiline comments into Java-Style multiline comments in Scala codes.
(All comment-only changes over 77 files: +786 lines, −747 lines)

## How was this patch tested?

Manual.

Author: Dongjoon Hyun <dongjoon@apache.org>

Closes #12130 from dongjoon-hyun/use_multiine_javadoc_comments.

4 files changed, 24 insertions, 20 deletions

diff --git a/streaming/src/main/scala/org/apache/spark/streaming/StreamingContext.scala b/streaming/src/main/scala/org/apache/spark/streaming/StreamingContext.scala
index c1e151d08b..ac37e8e022 100644
--- a/streaming/src/main/scala/org/apache/spark/streaming/StreamingContext.scala
+++ b/streaming/src/main/scala/org/apache/spark/streaming/StreamingContext.scala
@@ -497,9 +497,10 @@ class StreamingContext private[streaming] (
     new TransformedDStream[T](dstreams, sparkContext.clean(transformFunc))
   }
 
-  /** Add a [[org.apache.spark.streaming.scheduler.StreamingListener]] object for
-    * receiving system events related to streaming.
-    */
+  /**
+   * Add a [[org.apache.spark.streaming.scheduler.StreamingListener]] object for
+   * receiving system events related to streaming.
+   */
   def addStreamingListener(streamingListener: StreamingListener) {
     scheduler.listenerBus.addListener(streamingListener)
   }
diff --git a/streaming/src/main/scala/org/apache/spark/streaming/api/java/JavaStreamingContext.scala b/streaming/src/main/scala/org/apache/spark/streaming/api/java/JavaStreamingContext.scala
index 05f4da6fac..922e4a5e4d 100644
--- a/streaming/src/main/scala/org/apache/spark/streaming/api/java/JavaStreamingContext.scala
+++ b/streaming/src/main/scala/org/apache/spark/streaming/api/java/JavaStreamingContext.scala
@@ -517,9 +517,10 @@ class JavaStreamingContext(val ssc: StreamingContext) extends Closeable {
     ssc.remember(duration)
   }
 
-  /** Add a [[org.apache.spark.streaming.scheduler.StreamingListener]] object for
-    * receiving system events related to streaming.
-    */
+  /**
+   * Add a [[org.apache.spark.streaming.scheduler.StreamingListener]] object for
+   * receiving system events related to streaming.
+   */
   def addStreamingListener(streamingListener: StreamingListener) {
     ssc.addStreamingListener(streamingListener)
   }
diff --git a/streaming/src/main/scala/org/apache/spark/streaming/receiver/RateLimiter.scala b/streaming/src/main/scala/org/apache/spark/streaming/receiver/RateLimiter.scala
index 0a861f22b1..fbac4880bd 100644
--- a/streaming/src/main/scala/org/apache/spark/streaming/receiver/RateLimiter.scala
+++ b/streaming/src/main/scala/org/apache/spark/streaming/receiver/RateLimiter.scala
@@ -22,17 +22,18 @@ import com.google.common.util.concurrent.{RateLimiter => GuavaRateLimiter}
 import org.apache.spark.SparkConf
 import org.apache.spark.internal.Logging
 
-/** Provides waitToPush() method to limit the rate at which receivers consume data.
-  *
-  * waitToPush method will block the thread if too many messages have been pushed too quickly,
-  * and only return when a new message has been pushed. It assumes that only one message is
-  * pushed at a time.
-  *
-  * The spark configuration spark.streaming.receiver.maxRate gives the maximum number of messages
-  * per second that each receiver will accept.
-  *
-  * @param conf spark configuration
-  */
+/**
+ * Provides waitToPush() method to limit the rate at which receivers consume data.
+ *
+ * waitToPush method will block the thread if too many messages have been pushed too quickly,
+ * and only return when a new message has been pushed. It assumes that only one message is
+ * pushed at a time.
+ *
+ * The spark configuration spark.streaming.receiver.maxRate gives the maximum number of messages
+ * per second that each receiver will accept.
+ *
+ * @param conf spark configuration
+ */
 private[receiver] abstract class RateLimiter(conf: SparkConf) extends Logging {
 
   // treated as an upper limit
diff --git a/streaming/src/main/scala/org/apache/spark/streaming/scheduler/JobSet.scala b/streaming/src/main/scala/org/apache/spark/streaming/scheduler/JobSet.scala
index 66d5ffb797..0baedaf275 100644
--- a/streaming/src/main/scala/org/apache/spark/streaming/scheduler/JobSet.scala
+++ b/streaming/src/main/scala/org/apache/spark/streaming/scheduler/JobSet.scala
@@ -21,9 +21,10 @@ import scala.collection.mutable.HashSet
 
 import org.apache.spark.streaming.Time
 
-/** Class representing a set of Jobs
-  * belong to the same batch.
-  */
+/**
+ * Class representing a set of Jobs
+ * belong to the same batch.
+ */
 private[streaming]
 case class JobSet(
     time: Time,