Minor cleanup in ShuffleBlockManager

core/src/main/scala/org/apache/spark/storage/ShuffleBlockManager.scala

@@ -23,7 +23,6 @@ import java.util.concurrent.atomic.AtomicInteger
 
 import scala.collection.JavaConversions._
 
-import org.apache.spark.Logging
 import org.apache.spark.serializer.Serializer
 import org.apache.spark.util.{MetadataCleanerType, MetadataCleaner, TimeStampedHashMap}
 import org.apache.spark.util.collection.{PrimitiveKeyOpenHashMap, PrimitiveVector}
@@ -59,7 +58,7 @@ private[spark] trait ShuffleWriterGroup {
  * files within a ShuffleFileGroups associated with the block's reducer.
  */
 private[spark]
-class ShuffleBlockManager(blockManager: BlockManager) extends Logging {
+class ShuffleBlockManager(blockManager: BlockManager) {
   // Turning off shuffle file consolidation causes all shuffle Blocks to get their own file.
   // TODO: Remove this once the shuffle file consolidation feature is stable.
   val consolidateShuffleFiles =
@@ -83,7 +82,7 @@ class ShuffleBlockManager(blockManager: BlockManager) extends Logging {
   private
   val metadataCleaner = new MetadataCleaner(MetadataCleanerType.SHUFFLE_BLOCK_MANAGER, this.cleanup)
 
-  def forMapTask(shuffleId: Int, mapId: Int, numBuckets: Int, serializer: Serializer) =
+  def forMapTask(shuffleId: Int, mapId: Int, numBuckets: Int, serializer: Serializer) = {
     new ShuffleWriterGroup {
       shuffleStates.putIfAbsent(shuffleId, new ShuffleState())
       private val shuffleState = shuffleStates(shuffleId)
@@ -133,6 +132,7 @@ class ShuffleBlockManager(blockManager: BlockManager) extends Logging {
         shuffleState.unusedFileGroups.add(group)
       }
     }
+  }
 
   /**
    * Returns the physical file segment in which the given BlockId is located.
@@ -177,7 +177,7 @@ object ShuffleBlockManager {
      * Note: mapIdToIndex(mapId) returns the index of the mapper into the vector for every
      * reducer.
      */
-    private val blockOffsetsByReducer = Array.tabulate[PrimitiveVector[Long]](files.length) { _ =>
+    private val blockOffsetsByReducer = Array.fill[PrimitiveVector[Long]](files.length) {
       new PrimitiveVector[Long]()
     }