diff --git a/core/src/main/scala/org/apache/spark/deploy/FaultToleranceTest.scala b/core/src/main/scala/org/apache/spark/deploy/FaultToleranceTest.scala
index 668032a3a2680..0aa8852649e05 100644
--- a/core/src/main/scala/org/apache/spark/deploy/FaultToleranceTest.scala
+++ b/core/src/main/scala/org/apache/spark/deploy/FaultToleranceTest.scala
@@ -1,19 +1,19 @@
 /*
  *
- *  * Licensed to the Apache Software Foundation (ASF) under one or more
- *  * contributor license agreements.  See the NOTICE file distributed with
- *  * this work for additional information regarding copyright ownership.
- *  * The ASF licenses this file to You under the Apache License, Version 2.0
- *  * (the "License"); you may not use this file except in compliance with
- *  * the License.  You may obtain a copy of the License at
- *  *
- *  *    http://www.apache.org/licenses/LICENSE-2.0
- *  *
- *  * Unless required by applicable law or agreed to in writing, software
- *  * distributed under the License is distributed on an "AS IS" BASIS,
- *  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- *  * See the License for the specific language governing permissions and
- *  * limitations under the License.
+ *  Licensed to the Apache Software Foundation (ASF) under one or more
+ *  contributor license agreements.  See the NOTICE file distributed with
+ *  this work for additional information regarding copyright ownership.
+ *  The ASF licenses this file to You under the Apache License, Version 2.0
+ *  (the "License"); you may not use this file except in compliance with
+ *  the License.  You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
  *
  */
 
diff --git a/core/src/main/scala/org/apache/spark/network/netty/ShuffleCopier.scala b/core/src/main/scala/org/apache/spark/network/netty/ShuffleCopier.scala
index 481ff8c3e02d2..b1e1576dadc1a 100644
--- a/core/src/main/scala/org/apache/spark/network/netty/ShuffleCopier.scala
+++ b/core/src/main/scala/org/apache/spark/network/netty/ShuffleCopier.scala
@@ -76,7 +76,7 @@ private[spark] object ShuffleCopier extends Logging {
     extends FileClientHandler with Logging {
 
     override def handle(ctx: ChannelHandlerContext, in: ByteBuf, header: FileHeader) {
-      logDebug("Received Block: " + header.blockId + " (" + header.fileLen + "B)");
+      logDebug("Received Block: " + header.blockId + " (" + header.fileLen + "B)")
       resultCollectCallBack(header.blockId, header.fileLen.toLong, in.readBytes(header.fileLen))
     }
 
diff --git a/core/src/main/scala/org/apache/spark/rdd/CartesianRDD.scala b/core/src/main/scala/org/apache/spark/rdd/CartesianRDD.scala
index 9b0c882481cfc..0de22f0e06e49 100644
--- a/core/src/main/scala/org/apache/spark/rdd/CartesianRDD.scala
+++ b/core/src/main/scala/org/apache/spark/rdd/CartesianRDD.scala
@@ -70,7 +70,7 @@ class CartesianRDD[T: ClassManifest, U:ClassManifest](
   override def compute(split: Partition, context: TaskContext) = {
     val currSplit = split.asInstanceOf[CartesianPartition]
     for (x <- rdd1.iterator(currSplit.s1, context);
-      y <- rdd2.iterator(currSplit.s2, context)) yield (x, y)
+         y <- rdd2.iterator(currSplit.s2, context)) yield (x, y)
   }
 
   override def getDependencies: Seq[Dependency[_]] = List(
diff --git a/core/src/main/scala/org/apache/spark/ui/jobs/StagePage.scala b/core/src/main/scala/org/apache/spark/ui/jobs/StagePage.scala
index c8625716e9d8e..baccc4281a06c 100644
--- a/core/src/main/scala/org/apache/spark/ui/jobs/StagePage.scala
+++ b/core/src/main/scala/org/apache/spark/ui/jobs/StagePage.scala
@@ -133,7 +133,7 @@ private[spark] class StagePage(parent: JobProgressUI) {
         summary ++
         <h4>Summary Metrics for {numCompleted} Completed Tasks</h4> ++
         <div>{summaryTable.getOrElse("No tasks have reported metrics yet.")}</div> ++
-        <h4>Tasks</h4> ++ taskTable;
+        <h4>Tasks</h4> ++ taskTable
 
       headerSparkPage(content, parent.sc, "Details for Stage %d".format(stageId), Stages)
     }
diff --git a/core/src/test/scala/org/apache/spark/LocalSparkContext.scala b/core/src/test/scala/org/apache/spark/LocalSparkContext.scala
index 6ec124da9c7b1..03f7c0b43a71e 100644
--- a/core/src/test/scala/org/apache/spark/LocalSparkContext.scala
+++ b/core/src/test/scala/org/apache/spark/LocalSparkContext.scala
@@ -30,7 +30,7 @@ trait LocalSparkContext extends BeforeAndAfterEach with BeforeAndAfterAll { self
   @transient var sc: SparkContext = _
 
   override def beforeAll() {
-    InternalLoggerFactory.setDefaultFactory(new Slf4JLoggerFactory());
+    InternalLoggerFactory.setDefaultFactory(new Slf4JLoggerFactory())
     super.beforeAll()
   }
 
diff --git a/core/src/test/scala/org/apache/spark/PartitioningSuite.scala b/core/src/test/scala/org/apache/spark/PartitioningSuite.scala
index 7d938917f2650..1374d01774693 100644
--- a/core/src/test/scala/org/apache/spark/PartitioningSuite.scala
+++ b/core/src/test/scala/org/apache/spark/PartitioningSuite.scala
@@ -142,11 +142,11 @@ class PartitioningSuite extends FunSuite with SharedSparkContext {
         .filter(_ >= 0.0)
 
     // Run the partitions, including the consecutive empty ones, through StatCounter
-    val stats: StatCounter = rdd.stats();
-    assert(abs(6.0 - stats.sum) < 0.01);
-    assert(abs(6.0/2 - rdd.mean) < 0.01);
-    assert(abs(1.0 - rdd.variance) < 0.01);
-    assert(abs(1.0 - rdd.stdev) < 0.01);
+    val stats: StatCounter = rdd.stats()
+    assert(abs(6.0 - stats.sum) < 0.01)
+    assert(abs(6.0/2 - rdd.mean) < 0.01)
+    assert(abs(1.0 - rdd.variance) < 0.01)
+    assert(abs(1.0 - rdd.stdev) < 0.01)
 
     // Add other tests here for classes that should be able to handle empty partitions correctly
   }
diff --git a/examples/src/main/scala/org/apache/spark/examples/LocalALS.scala b/examples/src/main/scala/org/apache/spark/examples/LocalALS.scala
index 4af45b2b4a067..83db8b9e26411 100644
--- a/examples/src/main/scala/org/apache/spark/examples/LocalALS.scala
+++ b/examples/src/main/scala/org/apache/spark/examples/LocalALS.scala
@@ -120,7 +120,7 @@ object LocalALS {
         System.exit(1)
       }
     }
-    printf("Running with M=%d, U=%d, F=%d, iters=%d\n", M, U, F, ITERATIONS);
+    printf("Running with M=%d, U=%d, F=%d, iters=%d\n", M, U, F, ITERATIONS)
     
     val R = generateR()
 
diff --git a/examples/src/main/scala/org/apache/spark/examples/SparkTC.scala b/examples/src/main/scala/org/apache/spark/examples/SparkTC.scala
index 5a7a9d1bd8f74..8543ce0e3285e 100644
--- a/examples/src/main/scala/org/apache/spark/examples/SparkTC.scala
+++ b/examples/src/main/scala/org/apache/spark/examples/SparkTC.scala
@@ -65,7 +65,7 @@ object SparkTC {
       oldCount = nextCount
       // Perform the join, obtaining an RDD of (y, (z, x)) pairs,
       // then project the result to obtain the new (x, z) paths.
-      tc = tc.union(tc.join(edges).map(x => (x._2._2, x._2._1))).distinct().cache();
+      tc = tc.union(tc.join(edges).map(x => (x._2._2, x._2._1))).distinct().cache()
       nextCount = tc.count()
     } while (nextCount != oldCount)
 
diff --git a/examples/src/main/scala/org/apache/spark/streaming/examples/ActorWordCount.scala b/examples/src/main/scala/org/apache/spark/streaming/examples/ActorWordCount.scala
index cd3423a07b6b7..af52b7e9a12f1 100644
--- a/examples/src/main/scala/org/apache/spark/streaming/examples/ActorWordCount.scala
+++ b/examples/src/main/scala/org/apache/spark/streaming/examples/ActorWordCount.scala
@@ -120,7 +120,7 @@ object FeederActor {
 
     println("Feeder started as:" + feeder)
 
-    actorSystem.awaitTermination();
+    actorSystem.awaitTermination()
   }
 }
 
diff --git a/streaming/src/main/scala/org/apache/spark/streaming/Checkpoint.scala b/streaming/src/main/scala/org/apache/spark/streaming/Checkpoint.scala
index 2d8f07262426f..74069860c0e6e 100644
--- a/streaming/src/main/scala/org/apache/spark/streaming/Checkpoint.scala
+++ b/streaming/src/main/scala/org/apache/spark/streaming/Checkpoint.scala
@@ -92,7 +92,7 @@ class CheckpointWriter(checkpointDir: String) extends Logging {
           fs.delete(file, false)
           fs.rename(writeFile, file)
 
-          val finishTime = System.currentTimeMillis();
+          val finishTime = System.currentTimeMillis()
           logInfo("Checkpoint for time " + checkpointTime + " saved to file '" + file +
             "', took " + bytes.length + " bytes and " + (finishTime - startTime) + " milliseconds")
           return
@@ -122,7 +122,9 @@ class CheckpointWriter(checkpointDir: String) extends Logging {
 
   def stop() {
     synchronized {
-      if (stopped) return ;
+      if (stopped) {
+        return
+      }
       stopped = true
     }
     executor.shutdown()
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 cfc1c2628cb13..4f6d479401d61 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
@@ -17,7 +17,7 @@
 
 package org.apache.spark.streaming.api.java
 
-import java.lang.{Long => JLong, Integer => JInt}
+import java.lang.{Integer => JInt}
 import java.io.InputStream
 import java.util.{Map => JMap, List => JList}
 
@@ -33,10 +33,9 @@ import twitter4j.auth.Authorization
 import org.apache.spark.rdd.RDD
 import org.apache.spark.storage.StorageLevel
 import org.apache.spark.api.java.function.{Function => JFunction, Function2 => JFunction2}
-import org.apache.spark.api.java.{JavaPairRDD, JavaRDDLike, JavaSparkContext, JavaRDD}
+import org.apache.spark.api.java.{JavaPairRDD, JavaSparkContext, JavaRDD}
 import org.apache.spark.streaming._
 import org.apache.spark.streaming.dstream._
-import org.apache.spark.streaming.receivers.{ActorReceiver, ReceiverSupervisorStrategy}
 
 /**
  * A StreamingContext is the main entry point for Spark Streaming functionality. Besides the basic
@@ -302,7 +301,7 @@ class JavaStreamingContext(val ssc: StreamingContext) {
       implicitly[ClassManifest[AnyRef]].asInstanceOf[ClassManifest[V]]
     implicit val cmf: ClassManifest[F] =
       implicitly[ClassManifest[AnyRef]].asInstanceOf[ClassManifest[F]]
-    ssc.fileStream[K, V, F](directory);
+    ssc.fileStream[K, V, F](directory)
   }
 
   /**
diff --git a/streaming/src/main/scala/org/apache/spark/streaming/dstream/FlumeInputDStream.scala b/streaming/src/main/scala/org/apache/spark/streaming/dstream/FlumeInputDStream.scala
index 18de772946805..a0189eca043c6 100644
--- a/streaming/src/main/scala/org/apache/spark/streaming/dstream/FlumeInputDStream.scala
+++ b/streaming/src/main/scala/org/apache/spark/streaming/dstream/FlumeInputDStream.scala
@@ -137,8 +137,8 @@ class FlumeReceiver(
 
   protected override def onStart() {
     val responder = new SpecificResponder(
-      classOf[AvroSourceProtocol], new FlumeEventServer(this));
-    val server = new NettyServer(responder, new InetSocketAddress(host, port));
+      classOf[AvroSourceProtocol], new FlumeEventServer(this))
+    val server = new NettyServer(responder, new InetSocketAddress(host, port))
     blockGenerator.start()
     server.start()
     logInfo("Flume receiver started")
diff --git a/streaming/src/test/scala/org/apache/spark/streaming/InputStreamsSuite.scala b/streaming/src/test/scala/org/apache/spark/streaming/InputStreamsSuite.scala
index ca2da6816a139..f398263a10da5 100644
--- a/streaming/src/test/scala/org/apache/spark/streaming/InputStreamsSuite.scala
+++ b/streaming/src/test/scala/org/apache/spark/streaming/InputStreamsSuite.scala
@@ -124,9 +124,9 @@ class InputStreamsSuite extends TestSuiteBase with BeforeAndAfter {
     val clock = ssc.scheduler.clock.asInstanceOf[ManualClock]
     val input = Seq(1, 2, 3, 4, 5)
     Thread.sleep(1000)
-    val transceiver = new NettyTransceiver(new InetSocketAddress("localhost", testPort));
+    val transceiver = new NettyTransceiver(new InetSocketAddress("localhost", testPort))
     val client = SpecificRequestor.getClient(
-      classOf[AvroSourceProtocol], transceiver);
+      classOf[AvroSourceProtocol], transceiver)
 
     for (i <- 0 until input.size) {
       val event = new AvroFlumeEvent
diff --git a/streaming/src/test/scala/org/apache/spark/streaming/TestSuiteBase.scala b/streaming/src/test/scala/org/apache/spark/streaming/TestSuiteBase.scala
index be140699c2964..8c8c359e6e865 100644
--- a/streaming/src/test/scala/org/apache/spark/streaming/TestSuiteBase.scala
+++ b/streaming/src/test/scala/org/apache/spark/streaming/TestSuiteBase.scala
@@ -251,7 +251,7 @@ trait TestSuiteBase extends FunSuite with BeforeAndAfter with Logging {
 
       Thread.sleep(500) // Give some time for the forgetting old RDDs to complete
     } catch {
-      case e: Exception => e.printStackTrace(); throw e;
+      case e: Exception => {e.printStackTrace(); throw e}
     } finally {
       ssc.stop()
     }
diff --git a/yarn/src/main/scala/org/apache/spark/deploy/yarn/ApplicationMaster.scala b/yarn/src/main/scala/org/apache/spark/deploy/yarn/ApplicationMaster.scala
index 89b00415daa8e..a7baf0c36cfd4 100644
--- a/yarn/src/main/scala/org/apache/spark/deploy/yarn/ApplicationMaster.scala
+++ b/yarn/src/main/scala/org/apache/spark/deploy/yarn/ApplicationMaster.scala
@@ -21,6 +21,7 @@ import java.io.IOException
 import java.net.Socket
 import java.util.concurrent.CopyOnWriteArrayList
 import java.util.concurrent.atomic.{AtomicInteger, AtomicReference}
+
 import org.apache.hadoop.conf.Configuration
 import org.apache.hadoop.fs.{FileSystem, Path}
 import org.apache.hadoop.net.NetUtils
@@ -33,6 +34,7 @@ import org.apache.hadoop.yarn.ipc.YarnRPC
 import org.apache.hadoop.yarn.util.{ConverterUtils, Records}
 import org.apache.spark.{SparkContext, Logging}
 import org.apache.spark.util.Utils
+
 import scala.collection.JavaConversions._
 
 class ApplicationMaster(args: ApplicationMasterArguments, conf: Configuration) extends Logging {
@@ -65,7 +67,7 @@ class ApplicationMaster(args: ApplicationMasterArguments, conf: Configuration) e
     ShutdownHookManager.get().addShutdownHook(new AppMasterShutdownHook(this), 30)
     
     appAttemptId = getApplicationAttemptId()
-    isLastAMRetry = appAttemptId.getAttemptId() >= maxAppAttempts;
+    isLastAMRetry = appAttemptId.getAttemptId() >= maxAppAttempts
     resourceManager = registerWithResourceManager()
 
     // Workaround until hadoop moves to something which has
@@ -195,7 +197,7 @@ class ApplicationMaster(args: ApplicationMasterArguments, conf: Configuration) e
           successed = true
         } finally {
           logDebug("finishing main")
-          isLastAMRetry = true;
+          isLastAMRetry = true
           if (successed) {
             ApplicationMaster.this.finishApplicationMaster(FinalApplicationStatus.SUCCEEDED)
           } else {
diff --git a/yarn/src/main/scala/org/apache/spark/deploy/yarn/Client.scala b/yarn/src/main/scala/org/apache/spark/deploy/yarn/Client.scala
index 1078d5b826f67..94e353af2e954 100644
--- a/yarn/src/main/scala/org/apache/spark/deploy/yarn/Client.scala
+++ b/yarn/src/main/scala/org/apache/spark/deploy/yarn/Client.scala
@@ -17,14 +17,13 @@
 
 package org.apache.spark.deploy.yarn
 
-import java.net.{InetAddress, InetSocketAddress, UnknownHostException, URI}
+import java.net.{InetAddress, UnknownHostException, URI}
 import java.nio.ByteBuffer
 
 import org.apache.hadoop.conf.Configuration
 import org.apache.hadoop.fs.{FileContext, FileStatus, FileSystem, Path, FileUtil}
 import org.apache.hadoop.fs.permission.FsPermission
 import org.apache.hadoop.mapred.Master
-import org.apache.hadoop.net.NetUtils
 import org.apache.hadoop.io.DataOutputBuffer
 import org.apache.hadoop.security.UserGroupInformation
 import org.apache.hadoop.yarn.api._
@@ -40,9 +39,7 @@ import scala.collection.mutable.HashMap
 import scala.collection.mutable.Map
 import scala.collection.JavaConversions._
 
-import org.apache.spark.Logging 
-import org.apache.spark.util.Utils
-import org.apache.spark.deploy.SparkHadoopUtil
+import org.apache.spark.Logging
 
 class Client(conf: Configuration, args: ClientArguments) extends YarnClientImpl with Logging {
   
@@ -123,7 +120,7 @@ class Client(conf: Configuration, args: ClientArguments) extends YarnClientImpl
     
     // if we have requested more then the clusters max for a single resource then exit.
     if (args.workerMemory > maxMem) {
-      logError("the worker size is to large to run on this cluster " + args.workerMemory);
+      logError("the worker size is to large to run on this cluster " + args.workerMemory)
       System.exit(1)
     }
     val amMem = args.amMemory + YarnAllocationHandler.MEMORY_OVERHEAD
@@ -160,8 +157,8 @@ class Client(conf: Configuration, args: ClientArguments) extends YarnClientImpl
     var dstHost = dstUri.getHost()
     if ((srcHost != null) && (dstHost != null)) {
       try {
-        srcHost = InetAddress.getByName(srcHost).getCanonicalHostName();
-        dstHost = InetAddress.getByName(dstHost).getCanonicalHostName();
+        srcHost = InetAddress.getByName(srcHost).getCanonicalHostName()
+        dstHost = InetAddress.getByName(dstHost).getCanonicalHostName()
       } catch {
         case e: UnknownHostException =>
           return false
@@ -178,7 +175,7 @@ class Client(conf: Configuration, args: ClientArguments) extends YarnClientImpl
     if (srcUri.getPort() != dstUri.getPort()) {
       return false
     }
-    return true;
+    return true
   }
 
   /**
@@ -190,13 +187,13 @@ class Client(conf: Configuration, args: ClientArguments) extends YarnClientImpl
       replication: Short,
       setPerms: Boolean = false): Path = {
     val fs = FileSystem.get(conf)
-    val remoteFs = originalPath.getFileSystem(conf);
+    val remoteFs = originalPath.getFileSystem(conf)
     var newPath = originalPath
     if (! compareFs(remoteFs, fs)) {
       newPath = new Path(dstDir, originalPath.getName())
       logInfo("Uploading " + originalPath + " to " + newPath)
-      FileUtil.copy(remoteFs, originalPath, fs, newPath, false, conf);
-      fs.setReplication(newPath, replication);
+      FileUtil.copy(remoteFs, originalPath, fs, newPath, false, conf)
+      fs.setReplication(newPath, replication)
       if (setPerms) fs.setPermission(newPath, new FsPermission(APP_FILE_PERMISSION))
     } 
     // resolve any symlinks in the URI path so using a "current" symlink
@@ -214,7 +211,7 @@ class Client(conf: Configuration, args: ClientArguments) extends YarnClientImpl
     // Add them as local resources to the AM
     val fs = FileSystem.get(conf)
 
-    val delegTokenRenewer = Master.getMasterPrincipal(conf);
+    val delegTokenRenewer = Master.getMasterPrincipal(conf)
     if (UserGroupInformation.isSecurityEnabled()) {
       if (delegTokenRenewer == null || delegTokenRenewer.length() == 0) {
         logError("Can't get Master Kerberos principal for use as renewer")
@@ -226,7 +223,7 @@ class Client(conf: Configuration, args: ClientArguments) extends YarnClientImpl
 
     if (UserGroupInformation.isSecurityEnabled()) {
       val dstFs = dst.getFileSystem(conf)
-      dstFs.addDelegationTokens(delegTokenRenewer, credentials);
+      dstFs.addDelegationTokens(delegTokenRenewer, credentials)
     }
     val localResources = HashMap[String, LocalResource]()
     FileSystem.mkdirs(fs, dst, new FsPermission(STAGING_DIR_PERMISSION))
@@ -286,7 +283,7 @@ class Client(conf: Configuration, args: ClientArguments) extends YarnClientImpl
       }
     }
 
-    UserGroupInformation.getCurrentUser().addCredentials(credentials);
+    UserGroupInformation.getCurrentUser().addCredentials(credentials)
     return localResources
   }
   
@@ -366,7 +363,7 @@ class Client(conf: Configuration, args: ClientArguments) extends YarnClientImpl
     }
 
     // Command for the ApplicationMaster
-    var javaCommand = "java";
+    var javaCommand = "java"
     val javaHome = System.getenv("JAVA_HOME")
     if ((javaHome != null && !javaHome.isEmpty()) || env.isDefinedAt("JAVA_HOME")) {
       javaCommand = Environment.JAVA_HOME.$() + "/bin/java"
diff --git a/yarn/src/main/scala/org/apache/spark/deploy/yarn/ClientDistributedCacheManager.scala b/yarn/src/main/scala/org/apache/spark/deploy/yarn/ClientDistributedCacheManager.scala
index 674c8f8112b86..5f159b073f537 100644
--- a/yarn/src/main/scala/org/apache/spark/deploy/yarn/ClientDistributedCacheManager.scala
+++ b/yarn/src/main/scala/org/apache/spark/deploy/yarn/ClientDistributedCacheManager.scala
@@ -197,11 +197,11 @@ class ClientDistributedCacheManager() extends Logging {
    */
   def checkPermissionOfOther(fs: FileSystem, path: Path,
       action: FsAction, statCache: Map[URI, FileStatus]): Boolean = {
-    val status = getFileStatus(fs, path.toUri(), statCache);
+    val status = getFileStatus(fs, path.toUri(), statCache)
     val perms = status.getPermission()
     val otherAction = perms.getOtherAction()
     if (otherAction.implies(action)) {
-      return true;
+      return true
     }
     return false
   }
diff --git a/yarn/src/main/scala/org/apache/spark/deploy/yarn/WorkerRunnable.scala b/yarn/src/main/scala/org/apache/spark/deploy/yarn/WorkerRunnable.scala
index 7a66532254c74..a4d6e1d87d127 100644
--- a/yarn/src/main/scala/org/apache/spark/deploy/yarn/WorkerRunnable.scala
+++ b/yarn/src/main/scala/org/apache/spark/deploy/yarn/WorkerRunnable.scala
@@ -22,7 +22,7 @@ import java.nio.ByteBuffer
 import java.security.PrivilegedExceptionAction
 
 import org.apache.hadoop.conf.Configuration
-import org.apache.hadoop.fs.{FileStatus, FileSystem, Path}
+import org.apache.hadoop.fs.Path
 import org.apache.hadoop.io.DataOutputBuffer
 import org.apache.hadoop.net.NetUtils
 import org.apache.hadoop.security.UserGroupInformation
@@ -38,7 +38,6 @@ import scala.collection.JavaConversions._
 import scala.collection.mutable.HashMap
 
 import org.apache.spark.Logging
-import org.apache.spark.util.Utils
 
 class WorkerRunnable(container: Container, conf: Configuration, masterAddress: String,
     slaveId: String, hostname: String, workerMemory: Int, workerCores: Int) 
@@ -108,7 +107,7 @@ class WorkerRunnable(container: Container, conf: Configuration, masterAddress: S
     credentials.writeTokenStorageToStream(dob)
     ctx.setContainerTokens(ByteBuffer.wrap(dob.getData()))
 
-    var javaCommand = "java";
+    var javaCommand = "java"
     val javaHome = System.getenv("JAVA_HOME")
     if ((javaHome != null && !javaHome.isEmpty()) || env.isDefinedAt("JAVA_HOME")) {
       javaCommand = Environment.JAVA_HOME.$() + "/bin/java"
@@ -204,8 +203,8 @@ class WorkerRunnable(container: Container, conf: Configuration, masterAddress: S
 
     // use doAs and remoteUser here so we can add the container token and not 
     // pollute the current users credentials with all of the individual container tokens
-    val user = UserGroupInformation.createRemoteUser(container.getId().toString());
-    val containerToken = container.getContainerToken();
+    val user = UserGroupInformation.createRemoteUser(container.getId().toString())
+    val containerToken = container.getContainerToken()
     if (containerToken != null) {
       user.addToken(ProtoUtils.convertFromProtoFormat(containerToken, cmAddress))
     }
@@ -216,8 +215,8 @@ class WorkerRunnable(container: Container, conf: Configuration, masterAddress: S
             return rpc.getProxy(classOf[ContainerManager],
                 cmAddress, conf).asInstanceOf[ContainerManager]
           }
-        });
-    return proxy;
+        })
+    proxy
   }
   
 }
diff --git a/yarn/src/main/scala/org/apache/spark/deploy/yarn/YarnSparkHadoopUtil.scala b/yarn/src/main/scala/org/apache/spark/deploy/yarn/YarnSparkHadoopUtil.scala
index ca2f1e2565b9a..2ba2366ead171 100644
--- a/yarn/src/main/scala/org/apache/spark/deploy/yarn/YarnSparkHadoopUtil.scala
+++ b/yarn/src/main/scala/org/apache/spark/deploy/yarn/YarnSparkHadoopUtil.scala
@@ -18,13 +18,10 @@
 package org.apache.spark.deploy.yarn
 
 import org.apache.spark.deploy.SparkHadoopUtil
-import collection.mutable.HashMap
 import org.apache.hadoop.mapred.JobConf
 import org.apache.hadoop.security.UserGroupInformation
 import org.apache.hadoop.yarn.conf.YarnConfiguration
 import org.apache.hadoop.conf.Configuration
-import org.apache.hadoop.yarn.api.ApplicationConstants.Environment
-import java.security.PrivilegedExceptionAction
 
 /**
  * Contains util methods to interact with Hadoop from spark.
@@ -40,7 +37,7 @@ class YarnSparkHadoopUtil extends SparkHadoopUtil {
 
   // add any user credentials to the job conf which are necessary for running on a secure Hadoop cluster
   override def addCredentials(conf: JobConf) {
-    val jobCreds = conf.getCredentials();
+    val jobCreds = conf.getCredentials()
     jobCreds.mergeAll(UserGroupInformation.getCurrentUser().getCredentials())
   }
 }