Better fix to style issue.

Author: tdas

streaming/src/main/scala/org/apache/spark/streaming/rdd/WriteAheadLogBackedBlockRDD.scala

@@ -117,9 +117,9 @@ class WriteAheadLogBackedBlockRDD[T: ClassTag](
    */
   override def getPreferredLocations(split: Partition): Seq[String] = {
     val partition = split.asInstanceOf[WriteAheadLogBackedBlockRDDPartition]
-    def blockLocations = getBlockIdLocations().get(partition.blockId)
+    val blockLocations = getBlockIdLocations().get(partition.blockId)
     def segmentLocations = HdfsUtils.getFileSegmentLocations(
       partition.segment.path, partition.segment.offset, partition.segment.length, hadoopConfig)
-    blockLocations.orElse(segmentLocations).getOrElse(Seq.empty)
+    blockLocations.getOrElse(segmentLocations)
   }
 }

streaming/src/main/scala/org/apache/spark/streaming/util/HdfsUtils.scala

@@ -54,12 +54,12 @@ private[streaming] object HdfsUtils {
 
   /** Get the locations of the HDFS blocks containing the given file segment. */
   def getFileSegmentLocations(
-      path: String, offset: Long, length: Long, conf: Configuration): Option[Seq[String]] = {
+      path: String, offset: Long, length: Long, conf: Configuration): Array[String] = {
     val dfsPath = new Path(path)
     val dfs = getFileSystemForPath(dfsPath, conf)
     val fileStatus = dfs.getFileStatus(dfsPath)
     val blockLocs = Option(dfs.getFileBlockLocations(fileStatus, offset, length))
-    blockLocs.map(_.flatMap(_.getHosts))
+    blockLocs.map(_.flatMap(_.getHosts)).getOrElse(Array.empty)
   }
 
   def getFileSystemForPath(path: Path, conf: Configuration): FileSystem = {