[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.

1 files changed, 8 insertions, 7 deletions

diff --git a/external/flume/src/main/scala/org/apache/spark/streaming/flume/FlumeInputDStream.scala b/external/flume/src/main/scala/org/apache/spark/streaming/flume/FlumeInputDStream.scala
index 7dc9606913..6e7c3f358e 100644
--- a/external/flume/src/main/scala/org/apache/spark/streaming/flume/FlumeInputDStream.scala
+++ b/external/flume/src/main/scala/org/apache/spark/streaming/flume/FlumeInputDStream.scala
@@ -185,13 +185,14 @@ class FlumeReceiver(
 
   override def preferredLocation: Option[String] = Option(host)
 
-  /** A Netty Pipeline factory that will decompress incoming data from
-    * and the Netty client and compress data going back to the client.
-    *
-    * The compression on the return is required because Flume requires
-    * a successful response to indicate it can remove the event/batch
-    * from the configured channel
-    */
+  /**
+   * A Netty Pipeline factory that will decompress incoming data from
+   * and the Netty client and compress data going back to the client.
+   *
+   * The compression on the return is required because Flume requires
+   * a successful response to indicate it can remove the event/batch
+   * from the configured channel
+   */
   private[streaming]
   class CompressionChannelPipelineFactory extends ChannelPipelineFactory {
     def getPipeline(): ChannelPipeline = {