[SPARK-3873][TESTS] Import ordering fixes.

Author: Marcelo Vanzin <vanzin@cloudera.com>

Closes #10582 from vanzin/SPARK-3873-tests.

82 files changed, 176 insertions, 196 deletions

diff --git a/core/src/test/scala/org/apache/spark/ContextCleanerSuite.scala b/core/src/test/scala/org/apache/spark/ContextCleanerSuite.scala
index 0c14bef7be..7b02380917 100644
--- a/core/src/test/scala/org/apache/spark/ContextCleanerSuite.scala
+++ b/core/src/test/scala/org/apache/spark/ContextCleanerSuite.scala
@@ -24,18 +24,14 @@ import scala.language.existentials
 import scala.util.Random
 
 import org.scalatest.BeforeAndAfter
-import org.scalatest.concurrent.PatienceConfiguration
 import org.scalatest.concurrent.Eventually._
+import org.scalatest.concurrent.PatienceConfiguration
 import org.scalatest.time.SpanSugar._
 
-import org.apache.spark.rdd.{ReliableRDDCheckpointData, RDD}
-import org.apache.spark.storage._
+import org.apache.spark.rdd.{RDD, ReliableRDDCheckpointData}
 import org.apache.spark.shuffle.hash.HashShuffleManager
 import org.apache.spark.shuffle.sort.SortShuffleManager
-import org.apache.spark.storage.BroadcastBlockId
-import org.apache.spark.storage.RDDBlockId
-import org.apache.spark.storage.ShuffleBlockId
-import org.apache.spark.storage.ShuffleIndexBlockId
+import org.apache.spark.storage._
 
 /**
  * An abstract base class for context cleaner tests, which sets up a context with a config
diff --git a/core/src/test/scala/org/apache/spark/ExecutorAllocationManagerSuite.scala b/core/src/test/scala/org/apache/spark/ExecutorAllocationManagerSuite.scala
index fedfbd547b..4e678fbac6 100644
--- a/core/src/test/scala/org/apache/spark/ExecutorAllocationManagerSuite.scala
+++ b/core/src/test/scala/org/apache/spark/ExecutorAllocationManagerSuite.scala
@@ -20,6 +20,7 @@ package org.apache.spark
 import scala.collection.mutable
 
 import org.scalatest.{BeforeAndAfter, PrivateMethodTester}
+
 import org.apache.spark.executor.TaskMetrics
 import org.apache.spark.scheduler._
 import org.apache.spark.scheduler.cluster.ExecutorInfo
diff --git a/core/src/test/scala/org/apache/spark/FailureSuite.scala b/core/src/test/scala/org/apache/spark/FailureSuite.scala
index 203dab934c..3def8b0b18 100644
--- a/core/src/test/scala/org/apache/spark/FailureSuite.scala
+++ b/core/src/test/scala/org/apache/spark/FailureSuite.scala
@@ -17,10 +17,10 @@
 
 package org.apache.spark
 
-import org.apache.spark.util.NonSerializable
-
 import java.io.{IOException, NotSerializableException, ObjectInputStream}
 
+import org.apache.spark.util.NonSerializable
+
 // Common state shared by FailureSuite-launched tasks. We use a global object
 // for this because any local variables used in the task closures will rightfully
 // be copied for each task, so there's no other way for them to share state.
diff --git a/core/src/test/scala/org/apache/spark/FileServerSuite.scala b/core/src/test/scala/org/apache/spark/FileServerSuite.scala
index 2c32b69715..bc7059b77f 100644
--- a/core/src/test/scala/org/apache/spark/FileServerSuite.scala
+++ b/core/src/test/scala/org/apache/spark/FileServerSuite.scala
@@ -27,10 +27,10 @@ import org.apache.commons.lang3.RandomUtils
 
 import org.apache.spark.util.Utils
 
-import SSLSampleConfigs._
-
 class FileServerSuite extends SparkFunSuite with LocalSparkContext {
 
+  import SSLSampleConfigs._
+
   @transient var tmpDir: File = _
   @transient var tmpFile: File = _
   @transient var tmpJarUrl: String = _
diff --git a/core/src/test/scala/org/apache/spark/FileSuite.scala b/core/src/test/scala/org/apache/spark/FileSuite.scala
index 2e47801aaf..993834f8d7 100644
--- a/core/src/test/scala/org/apache/spark/FileSuite.scala
+++ b/core/src/test/scala/org/apache/spark/FileSuite.scala
@@ -21,17 +21,16 @@ import java.io.{File, FileWriter}
 
 import scala.io.Source
 
-import org.apache.spark.input.PortableDataStream
-import org.apache.spark.storage.StorageLevel
-
 import org.apache.hadoop.io._
 import org.apache.hadoop.io.compress.DefaultCodec
-import org.apache.hadoop.mapred.{JobConf, FileAlreadyExistsException, FileSplit, TextInputFormat, TextOutputFormat}
+import org.apache.hadoop.mapred.{FileAlreadyExistsException, FileSplit, JobConf, TextInputFormat, TextOutputFormat}
 import org.apache.hadoop.mapreduce.Job
 import org.apache.hadoop.mapreduce.lib.input.{FileSplit => NewFileSplit, TextInputFormat => NewTextInputFormat}
 import org.apache.hadoop.mapreduce.lib.output.{TextOutputFormat => NewTextOutputFormat}
 
-import org.apache.spark.rdd.{NewHadoopRDD, HadoopRDD}
+import org.apache.spark.input.PortableDataStream
+import org.apache.spark.rdd.{HadoopRDD, NewHadoopRDD}
+import org.apache.spark.storage.StorageLevel
 import org.apache.spark.util.Utils
 
 class FileSuite extends SparkFunSuite with LocalSparkContext {
diff --git a/core/src/test/scala/org/apache/spark/HeartbeatReceiverSuite.scala b/core/src/test/scala/org/apache/spark/HeartbeatReceiverSuite.scala
index 9b43341576..18e5350840 100644
--- a/core/src/test/scala/org/apache/spark/HeartbeatReceiverSuite.scala
+++ b/core/src/test/scala/org/apache/spark/HeartbeatReceiverSuite.scala
@@ -25,13 +25,13 @@ import scala.concurrent.Await
 import scala.concurrent.duration._
 import scala.language.postfixOps
 
-import org.scalatest.{BeforeAndAfterEach, PrivateMethodTester}
-import org.mockito.Mockito.{mock, spy, verify, when}
 import org.mockito.Matchers
 import org.mockito.Matchers._
+import org.mockito.Mockito.{mock, spy, verify, when}
+import org.scalatest.{BeforeAndAfterEach, PrivateMethodTester}
 
 import org.apache.spark.executor.TaskMetrics
-import org.apache.spark.rpc.{RpcCallContext, RpcEndpoint, RpcEnv, RpcEndpointRef}
+import org.apache.spark.rpc.{RpcCallContext, RpcEndpoint, RpcEndpointRef, RpcEnv}
 import org.apache.spark.scheduler._
 import org.apache.spark.scheduler.cluster.CoarseGrainedClusterMessages._
 import org.apache.spark.scheduler.cluster.CoarseGrainedSchedulerBackend
diff --git a/core/src/test/scala/org/apache/spark/LocalSparkContext.scala b/core/src/test/scala/org/apache/spark/LocalSparkContext.scala
index 214681970a..e1a0bf7c93 100644
--- a/core/src/test/scala/org/apache/spark/LocalSparkContext.scala
+++ b/core/src/test/scala/org/apache/spark/LocalSparkContext.scala
@@ -17,7 +17,7 @@
 
 package org.apache.spark
 
-import _root_.io.netty.util.internal.logging.{Slf4JLoggerFactory, InternalLoggerFactory}
+import _root_.io.netty.util.internal.logging.{InternalLoggerFactory, Slf4JLoggerFactory}
 import org.scalatest.BeforeAndAfterAll
 import org.scalatest.BeforeAndAfterEach
 import org.scalatest.Suite
diff --git a/core/src/test/scala/org/apache/spark/MapOutputTrackerSuite.scala b/core/src/test/scala/org/apache/spark/MapOutputTrackerSuite.scala
index 5b29d69cd9..3819c0a8f3 100644
--- a/core/src/test/scala/org/apache/spark/MapOutputTrackerSuite.scala
+++ b/core/src/test/scala/org/apache/spark/MapOutputTrackerSuite.scala
@@ -19,10 +19,10 @@ package org.apache.spark
 
 import scala.collection.mutable.ArrayBuffer
 
-import org.mockito.Mockito._
 import org.mockito.Matchers.{any, isA}
+import org.mockito.Mockito._
 
-import org.apache.spark.rpc.{RpcAddress, RpcEndpointRef, RpcCallContext, RpcEnv}
+import org.apache.spark.rpc.{RpcAddress, RpcCallContext, RpcEndpointRef, RpcEnv}
 import org.apache.spark.scheduler.{CompressedMapStatus, MapStatus}
 import org.apache.spark.shuffle.FetchFailedException
 import org.apache.spark.storage.{BlockManagerId, ShuffleBlockId}
diff --git a/core/src/test/scala/org/apache/spark/SSLOptionsSuite.scala b/core/src/test/scala/org/apache/spark/SSLOptionsSuite.scala
index 25b79bce6a..fa35819f55 100644
--- a/core/src/test/scala/org/apache/spark/SSLOptionsSuite.scala
+++ b/core/src/test/scala/org/apache/spark/SSLOptionsSuite.scala
@@ -21,9 +21,10 @@ import java.io.File
 import javax.net.ssl.SSLContext
 
 import com.google.common.io.Files
-import org.apache.spark.util.Utils
 import org.scalatest.BeforeAndAfterAll
 
+import org.apache.spark.util.Utils
+
 class SSLOptionsSuite extends SparkFunSuite with BeforeAndAfterAll {
 
   test("test resolving property file as spark conf ") {
diff --git a/core/src/test/scala/org/apache/spark/ShuffleSuite.scala b/core/src/test/scala/org/apache/spark/ShuffleSuite.scala
index 0de10ae485..c45d81459e 100644
--- a/core/src/test/scala/org/apache/spark/ShuffleSuite.scala
+++ b/core/src/test/scala/org/apache/spark/ShuffleSuite.scala
@@ -17,17 +17,17 @@
 
 package org.apache.spark
 
-import java.util.concurrent.{Callable, Executors, ExecutorService, CyclicBarrier}
+import java.util.concurrent.{Callable, CyclicBarrier, Executors, ExecutorService}
 
 import org.scalatest.Matchers
 
 import org.apache.spark.ShuffleSuite.NonJavaSerializableClass
 import org.apache.spark.memory.TaskMemoryManager
 import org.apache.spark.rdd.{CoGroupedRDD, OrderedRDDFunctions, RDD, ShuffledRDD, SubtractedRDD}
-import org.apache.spark.scheduler.{MyRDD, MapStatus, SparkListener, SparkListenerTaskEnd}
+import org.apache.spark.scheduler.{MapStatus, MyRDD, SparkListener, SparkListenerTaskEnd}
 import org.apache.spark.serializer.KryoSerializer
 import org.apache.spark.shuffle.ShuffleWriter
-import org.apache.spark.storage.{ShuffleDataBlockId, ShuffleBlockId}
+import org.apache.spark.storage.{ShuffleBlockId, ShuffleDataBlockId}
 import org.apache.spark.util.MutablePair
 
 abstract class ShuffleSuite extends SparkFunSuite with Matchers with LocalSparkContext {
diff --git a/core/src/test/scala/org/apache/spark/SortShuffleSuite.scala b/core/src/test/scala/org/apache/spark/SortShuffleSuite.scala
index 5354731465..7a897c2b46 100644
--- a/core/src/test/scala/org/apache/spark/SortShuffleSuite.scala
+++ b/core/src/test/scala/org/apache/spark/SortShuffleSuite.scala
@@ -26,8 +26,8 @@ import org.apache.commons.io.filefilter.TrueFileFilter
 import org.scalatest.BeforeAndAfterAll
 
 import org.apache.spark.rdd.ShuffledRDD
-import org.apache.spark.shuffle.sort.SortShuffleManager
 import org.apache.spark.serializer.{JavaSerializer, KryoSerializer}
+import org.apache.spark.shuffle.sort.SortShuffleManager
 import org.apache.spark.util.Utils
 
 class SortShuffleSuite extends ShuffleSuite with BeforeAndAfterAll {
diff --git a/core/src/test/scala/org/apache/spark/SparkConfSuite.scala b/core/src/test/scala/org/apache/spark/SparkConfSuite.scala
index ff9a92cc0a..2fe99e3f81 100644
--- a/core/src/test/scala/org/apache/spark/SparkConfSuite.scala
+++ b/core/src/test/scala/org/apache/spark/SparkConfSuite.scala
@@ -17,17 +17,18 @@
 
 package org.apache.spark
 
-import java.util.concurrent.{TimeUnit, Executors}
+import java.util.concurrent.{Executors, TimeUnit}
 
 import scala.collection.JavaConverters._
 import scala.concurrent.duration._
 import scala.language.postfixOps
-import scala.util.{Try, Random}
+import scala.util.{Random, Try}
+
+import com.esotericsoftware.kryo.Kryo
 
 import org.apache.spark.network.util.ByteUnit
 import org.apache.spark.serializer.{KryoRegistrator, KryoSerializer}
-import org.apache.spark.util.{RpcUtils, ResetSystemProperties}
-import com.esotericsoftware.kryo.Kryo
+import org.apache.spark.util.{ResetSystemProperties, RpcUtils}
 
 class SparkConfSuite extends SparkFunSuite with LocalSparkContext with ResetSystemProperties {
   test("Test byteString conversion") {
diff --git a/core/src/test/scala/org/apache/spark/SparkContextInfoSuite.scala b/core/src/test/scala/org/apache/spark/SparkContextInfoSuite.scala
index 2bdbd70c63..3706455c3f 100644
--- a/core/src/test/scala/org/apache/spark/SparkContextInfoSuite.scala
+++ b/core/src/test/scala/org/apache/spark/SparkContextInfoSuite.scala
@@ -18,6 +18,7 @@
 package org.apache.spark
 
 import org.scalatest.Assertions
+
 import org.apache.spark.storage.StorageLevel
 
 class SparkContextInfoSuite extends SparkFunSuite with LocalSparkContext {
diff --git a/core/src/test/scala/org/apache/spark/SparkContextSchedulerCreationSuite.scala b/core/src/test/scala/org/apache/spark/SparkContextSchedulerCreationSuite.scala
index d18e0782c0..52919c1ec0 100644
--- a/core/src/test/scala/org/apache/spark/SparkContextSchedulerCreationSuite.scala
+++ b/core/src/test/scala/org/apache/spark/SparkContextSchedulerCreationSuite.scala
@@ -19,11 +19,11 @@ package org.apache.spark
 
 import org.scalatest.PrivateMethodTester
 
-import org.apache.spark.util.Utils
 import org.apache.spark.scheduler.{SchedulerBackend, TaskScheduler, TaskSchedulerImpl}
 import org.apache.spark.scheduler.cluster.{SimrSchedulerBackend, SparkDeploySchedulerBackend}
 import org.apache.spark.scheduler.cluster.mesos.{CoarseMesosSchedulerBackend, MesosSchedulerBackend}
 import org.apache.spark.scheduler.local.LocalBackend
+import org.apache.spark.util.Utils
 
 class SparkContextSchedulerCreationSuite
   extends SparkFunSuite with LocalSparkContext with PrivateMethodTester with Logging {
diff --git a/core/src/test/scala/org/apache/spark/SparkContextSuite.scala b/core/src/test/scala/org/apache/spark/SparkContextSuite.scala
index 172ef050cc..556afd08bb 100644
--- a/core/src/test/scala/org/apache/spark/SparkContextSuite.scala
+++ b/core/src/test/scala/org/apache/spark/SparkContextSuite.scala
@@ -20,18 +20,18 @@ package org.apache.spark
 import java.io.File
 import java.util.concurrent.TimeUnit
 
+import scala.concurrent.Await
+import scala.concurrent.duration.Duration
+
 import com.google.common.base.Charsets._
 import com.google.common.io.Files
-
 import org.apache.hadoop.io.{BytesWritable, LongWritable, Text}
 import org.apache.hadoop.mapred.TextInputFormat
 import org.apache.hadoop.mapreduce.lib.input.{TextInputFormat => NewTextInputFormat}
-import org.apache.spark.util.Utils
-
-import scala.concurrent.Await
-import scala.concurrent.duration.Duration
 import org.scalatest.Matchers._
 
+import org.apache.spark.util.Utils
+
 class SparkContextSuite extends SparkFunSuite with LocalSparkContext {
 
   test("Only one SparkContext may be active at a time") {
diff --git a/core/src/test/scala/org/apache/spark/ThreadingSuite.scala b/core/src/test/scala/org/apache/spark/ThreadingSuite.scala
index 54c131cdae..fc31b784c7 100644
--- a/core/src/test/scala/org/apache/spark/ThreadingSuite.scala
+++ b/core/src/test/scala/org/apache/spark/ThreadingSuite.scala
@@ -17,9 +17,8 @@
 
 package org.apache.spark
 
-import java.util.concurrent.{TimeUnit, Semaphore}
-import java.util.concurrent.atomic.AtomicBoolean
-import java.util.concurrent.atomic.AtomicInteger
+import java.util.concurrent.{Semaphore, TimeUnit}
+import java.util.concurrent.atomic.{AtomicBoolean, AtomicInteger}
 
 import org.apache.spark.scheduler._
 
diff --git a/core/src/test/scala/org/apache/spark/api/python/PythonBroadcastSuite.scala b/core/src/test/scala/org/apache/spark/api/python/PythonBroadcastSuite.scala
index 135c56bf5b..b38a3667ab 100644
--- a/core/src/test/scala/org/apache/spark/api/python/PythonBroadcastSuite.scala
+++ b/core/src/test/scala/org/apache/spark/api/python/PythonBroadcastSuite.scala
@@ -17,9 +17,9 @@
 
 package org.apache.spark.api.python
 
-import scala.io.Source
+import java.io.{File, PrintWriter}
 
-import java.io.{PrintWriter, File}
+import scala.io.Source
 
 import org.scalatest.Matchers
 
diff --git a/core/src/test/scala/org/apache/spark/deploy/DeployTestUtils.scala b/core/src/test/scala/org/apache/spark/deploy/DeployTestUtils.scala
index 3164760b08..86455a13d0 100644
--- a/core/src/test/scala/org/apache/spark/deploy/DeployTestUtils.scala
+++ b/core/src/test/scala/org/apache/spark/deploy/DeployTestUtils.scala
@@ -20,9 +20,9 @@ package org.apache.spark.deploy
 import java.io.File
 import java.util.Date
 
+import org.apache.spark.{SecurityManager, SparkConf}
 import org.apache.spark.deploy.master.{ApplicationInfo, DriverInfo, WorkerInfo}
 import org.apache.spark.deploy.worker.{DriverRunner, ExecutorRunner}
-import org.apache.spark.{SecurityManager, SparkConf}
 
 private[deploy] object DeployTestUtils {
   def createAppDesc(): ApplicationDescription = {
diff --git a/core/src/test/scala/org/apache/spark/deploy/IvyTestUtils.scala b/core/src/test/scala/org/apache/spark/deploy/IvyTestUtils.scala
index d93febcfd2..9ecf49b598 100644
--- a/core/src/test/scala/org/apache/spark/deploy/IvyTestUtils.scala
+++ b/core/src/test/scala/org/apache/spark/deploy/IvyTestUtils.scala
@@ -24,10 +24,8 @@ import java.util.jar.Manifest
 
 import scala.collection.mutable.ArrayBuffer
 
-import com.google.common.io.{Files, ByteStreams}
-
+import com.google.common.io.{ByteStreams, Files}
 import org.apache.commons.io.FileUtils
-
 import org.apache.ivy.core.settings.IvySettings
 
 import org.apache.spark.TestUtils.{createCompiledClass, JavaSourceFromString}
diff --git a/core/src/test/scala/org/apache/spark/deploy/JsonProtocolSuite.scala b/core/src/test/scala/org/apache/spark/deploy/JsonProtocolSuite.scala
index 0a9f128a3a..2d48e75cfb 100644
--- a/core/src/test/scala/org/apache/spark/deploy/JsonProtocolSuite.scala
+++ b/core/src/test/scala/org/apache/spark/deploy/JsonProtocolSuite.scala
@@ -23,10 +23,10 @@ import com.fasterxml.jackson.core.JsonParseException
 import org.json4s._
 import org.json4s.jackson.JsonMethods
 
+import org.apache.spark.{JsonTestUtils, SparkFunSuite}
 import org.apache.spark.deploy.DeployMessages.{MasterStateResponse, WorkerStateResponse}
 import org.apache.spark.deploy.master.{ApplicationInfo, RecoveryState}
 import org.apache.spark.deploy.worker.ExecutorRunner
-import org.apache.spark.{JsonTestUtils, SparkFunSuite}
 
 class JsonProtocolSuite extends SparkFunSuite with JsonTestUtils {
 
diff --git a/core/src/test/scala/org/apache/spark/deploy/LogUrlsStandaloneSuite.scala b/core/src/test/scala/org/apache/spark/deploy/LogUrlsStandaloneSuite.scala
index 8dd31b4b6f..f416ace5c2 100644
--- a/core/src/test/scala/org/apache/spark/deploy/LogUrlsStandaloneSuite.scala
+++ b/core/src/test/scala/org/apache/spark/deploy/LogUrlsStandaloneSuite.scala
@@ -22,9 +22,9 @@ import java.net.URL
 import scala.collection.mutable
 import scala.io.Source
 
-import org.apache.spark.scheduler.cluster.ExecutorInfo
-import org.apache.spark.scheduler.{SparkListenerExecutorAdded, SparkListener}
 import org.apache.spark.{LocalSparkContext, SparkConf, SparkContext, SparkFunSuite}
+import org.apache.spark.scheduler.{SparkListener, SparkListenerExecutorAdded}
+import org.apache.spark.scheduler.cluster.ExecutorInfo
 import org.apache.spark.util.SparkConfWithEnv
 
 class LogUrlsStandaloneSuite extends SparkFunSuite with LocalSparkContext {
diff --git a/core/src/test/scala/org/apache/spark/deploy/RPackageUtilsSuite.scala b/core/src/test/scala/org/apache/spark/deploy/RPackageUtilsSuite.scala
index cc30ba223e..13cba94578 100644
--- a/core/src/test/scala/org/apache/spark/deploy/RPackageUtilsSuite.scala
+++ b/core/src/test/scala/org/apache/spark/deploy/RPackageUtilsSuite.scala
@@ -17,10 +17,10 @@
 
 package org.apache.spark.deploy
 
-import java.io.{PrintStream, OutputStream, File}
+import java.io.{File, OutputStream, PrintStream}
 import java.net.URI
-import java.util.jar.Attributes.Name
 import java.util.jar.{JarFile, Manifest}
+import java.util.jar.Attributes.Name
 import java.util.zip.ZipFile
 
 import scala.collection.JavaConverters._
diff --git a/core/src/test/scala/org/apache/spark/deploy/SparkSubmitUtilsSuite.scala b/core/src/test/scala/org/apache/spark/deploy/SparkSubmitUtilsSuite.scala
index 4b5039b668..4877710c12 100644
--- a/core/src/test/scala/org/apache/spark/deploy/SparkSubmitUtilsSuite.scala
+++ b/core/src/test/scala/org/apache/spark/deploy/SparkSubmitUtilsSuite.scala
@@ -17,14 +17,14 @@
 
 package org.apache.spark.deploy
 
-import java.io.{File, PrintStream, OutputStream}
+import java.io.{File, OutputStream, PrintStream}
 
 import scala.collection.mutable.ArrayBuffer
-import org.scalatest.BeforeAndAfterAll
 
 import org.apache.ivy.core.module.descriptor.MDArtifact
 import org.apache.ivy.core.settings.IvySettings
 import org.apache.ivy.plugins.resolver.{AbstractResolver, FileSystemResolver, IBiblioResolver}
+import org.scalatest.BeforeAndAfterAll
 
 import org.apache.spark.SparkFunSuite
 import org.apache.spark.deploy.SparkSubmitUtils.MavenCoordinate
diff --git a/core/src/test/scala/org/apache/spark/deploy/history/FsHistoryProviderSuite.scala b/core/src/test/scala/org/apache/spark/deploy/history/FsHistoryProviderSuite.scala
index 5cab17f8a3..6cbf911395 100644
--- a/core/src/test/scala/org/apache/spark/deploy/history/FsHistoryProviderSuite.scala
+++ b/core/src/test/scala/org/apache/spark/deploy/history/FsHistoryProviderSuite.scala
@@ -23,8 +23,8 @@ import java.net.URI
 import java.util.concurrent.TimeUnit
 import java.util.zip.{ZipInputStream, ZipOutputStream}
 
-import scala.io.Source
 import scala.concurrent.duration._
+import scala.io.Source
 import scala.language.postfixOps
 
 import com.google.common.base.Charsets
diff --git a/core/src/test/scala/org/apache/spark/deploy/master/PersistenceEngineSuite.scala b/core/src/test/scala/org/apache/spark/deploy/master/PersistenceEngineSuite.scala
index 7a44728675..b4deed7f87 100644
--- a/core/src/test/scala/org/apache/spark/deploy/master/PersistenceEngineSuite.scala
+++ b/core/src/test/scala/org/apache/spark/deploy/master/PersistenceEngineSuite.scala
@@ -25,7 +25,7 @@ import org.apache.curator.test.TestingServer
 
 import org.apache.spark.{SecurityManager, SparkConf, SparkFunSuite}
 import org.apache.spark.rpc.{RpcEndpoint, RpcEnv}
-import org.apache.spark.serializer.{Serializer, JavaSerializer}
+import org.apache.spark.serializer.{JavaSerializer, Serializer}
 import org.apache.spark.util.Utils
 
 class PersistenceEngineSuite extends SparkFunSuite {
diff --git a/core/src/test/scala/org/apache/spark/deploy/master/ui/MasterWebUISuite.scala b/core/src/test/scala/org/apache/spark/deploy/master/ui/MasterWebUISuite.scala
index fba835f054..0c9382a92b 100644
--- a/core/src/test/scala/org/apache/spark/deploy/master/ui/MasterWebUISuite.scala
+++ b/core/src/test/scala/org/apache/spark/deploy/master/ui/MasterWebUISuite.scala
@@ -23,11 +23,11 @@ import scala.io.Source
 import scala.language.postfixOps
 
 import org.json4s.jackson.JsonMethods._
-import org.json4s.JsonAST.{JNothing, JString, JInt}
+import org.json4s.JsonAST.{JInt, JNothing, JString}
 import org.mockito.Mockito.{mock, when}
 import org.scalatest.BeforeAndAfter
 
-import org.apache.spark.{SparkConf, SecurityManager, SparkFunSuite}
+import org.apache.spark.{SecurityManager, SparkConf, SparkFunSuite}
 import org.apache.spark.deploy.DeployMessages.MasterStateResponse
 import org.apache.spark.deploy.DeployTestUtils._
 import org.apache.spark.deploy.master._
diff --git a/core/src/test/scala/org/apache/spark/deploy/rest/StandaloneRestSubmitSuite.scala b/core/src/test/scala/org/apache/spark/deploy/rest/StandaloneRestSubmitSuite.scala
index fa39aa2cb1..ee889bf144 100644
--- a/core/src/test/scala/org/apache/spark/deploy/rest/StandaloneRestSubmitSuite.scala
+++ b/core/src/test/scala/org/apache/spark/deploy/rest/StandaloneRestSubmitSuite.scala
@@ -24,16 +24,16 @@ import javax.servlet.http.HttpServletResponse
 import scala.collection.mutable
 
 import com.google.common.base.Charsets
-import org.scalatest.BeforeAndAfterEach
 import org.json4s.JsonAST._
 import org.json4s.jackson.JsonMethods._
+import org.scalatest.BeforeAndAfterEach
 
 import org.apache.spark._
-import org.apache.spark.rpc._
-import org.apache.spark.util.Utils
-import org.apache.spark.deploy.DeployMessages._
 import org.apache.spark.deploy.{SparkSubmit, SparkSubmitArguments}
+import org.apache.spark.deploy.DeployMessages._
 import org.apache.spark.deploy.master.DriverState._
+import org.apache.spark.rpc._
+import org.apache.spark.util.Utils
 
 /**
  * Tests for the REST application submission protocol used in standalone cluster mode.
diff --git a/core/src/test/scala/org/apache/spark/deploy/worker/CommandUtilsSuite.scala b/core/src/test/scala/org/apache/spark/deploy/worker/CommandUtilsSuite.scala
index 7101cb9978..607c0a4fac 100644
--- a/core/src/test/scala/org/apache/spark/deploy/worker/CommandUtilsSuite.scala
+++ b/core/src/test/scala/org/apache/spark/deploy/worker/CommandUtilsSuite.scala
@@ -17,10 +17,11 @@
 
 package org.apache.spark.deploy.worker
 
+import org.scalatest.{Matchers, PrivateMethodTester}
+
 import org.apache.spark.{SecurityManager, SparkConf, SparkFunSuite}
 import org.apache.spark.deploy.Command
 import org.apache.spark.util.Utils
-import org.scalatest.{Matchers, PrivateMethodTester}
 
 class CommandUtilsSuite extends SparkFunSuite with Matchers with PrivateMethodTester {
 
diff --git a/core/src/test/scala/org/apache/spark/deploy/worker/DriverRunnerTest.scala b/core/src/test/scala/org/apache/spark/deploy/worker/DriverRunnerTest.scala
index 6258c18d17..bd8b0655f4 100644
--- a/core/src/test/scala/org/apache/spark/deploy/worker/DriverRunnerTest.scala
+++ b/core/src/test/scala/org/apache/spark/deploy/worker/DriverRunnerTest.scala
@@ -19,8 +19,8 @@ package org.apache.spark.deploy.worker
 
 import java.io.File
 
-import org.mockito.Mockito._
 import org.mockito.Matchers._
+import org.mockito.Mockito._
 import org.mockito.invocation.InvocationOnMock
 import org.mockito.stubbing.Answer
 
diff --git a/core/src/test/scala/org/apache/spark/deploy/worker/ExecutorRunnerTest.scala b/core/src/test/scala/org/apache/spark/deploy/worker/ExecutorRunnerTest.scala
index 98664dc110..0240bf8aed 100644
--- a/core/src/test/scala/org/apache/spark/deploy/worker/ExecutorRunnerTest.scala
+++ b/core/src/test/scala/org/apache/spark/deploy/worker/ExecutorRunnerTest.scala
@@ -19,8 +19,8 @@ package org.apache.spark.deploy.worker
 
 import java.io.File
 
-import org.apache.spark.deploy.{ApplicationDescription, Command, ExecutorState}
 import org.apache.spark.{SecurityManager, SparkConf, SparkFunSuite}
+import org.apache.spark.deploy.{ApplicationDescription, Command, ExecutorState}
 
 class ExecutorRunnerTest extends SparkFunSuite {
   test("command includes appId") {
diff --git a/core/src/test/scala/org/apache/spark/deploy/worker/WorkerSuite.scala b/core/src/test/scala/org/apache/spark/deploy/worker/WorkerSuite.scala
index 082d5e86eb..101a44edd8 100644
--- a/core/src/test/scala/org/apache/spark/deploy/worker/WorkerSuite.scala
+++ b/core/src/test/scala/org/apache/spark/deploy/worker/WorkerSuite.scala
@@ -19,11 +19,11 @@ package org.apache.spark.deploy.worker
 
 import org.scalatest.Matchers
 
+import org.apache.spark.{SecurityManager, SparkConf, SparkFunSuite}
+import org.apache.spark.deploy.{Command, ExecutorState}
 import org.apache.spark.deploy.DeployMessages.{DriverStateChanged, ExecutorStateChanged}
 import org.apache.spark.deploy.master.DriverState
-import org.apache.spark.deploy.{Command, ExecutorState}
 import org.apache.spark.rpc.{RpcAddress, RpcEnv}
-import org.apache.spark.{SecurityManager, SparkConf, SparkFunSuite}
 
 class WorkerSuite extends SparkFunSuite with Matchers {
 
diff --git a/core/src/test/scala/org/apache/spark/deploy/worker/WorkerWatcherSuite.scala b/core/src/test/scala/org/apache/spark/deploy/worker/WorkerWatcherSuite.scala
index 0ffd91d8ff..31bea3293a 100644
--- a/core/src/test/scala/org/apache/spark/deploy/worker/WorkerWatcherSuite.scala
+++ b/core/src/test/scala/org/apache/spark/deploy/worker/WorkerWatcherSuite.scala
@@ -17,9 +17,8 @@
 
 package org.apache.spark.deploy.worker
 
-import org.apache.spark.{SparkConf, SparkFunSuite}
-import org.apache.spark.SecurityManager
-import org.apache.spark.rpc.{RpcEndpointAddress, RpcAddress, RpcEnv}
+import org.apache.spark.{SecurityManager, SparkConf, SparkFunSuite}
+import org.apache.spark.rpc.{RpcAddress, RpcEndpointAddress, RpcEnv}
 
 class WorkerWatcherSuite extends SparkFunSuite {
   test("WorkerWatcher shuts down on valid disassociation") {
diff --git a/core/src/test/scala/org/apache/spark/input/WholeTextFileRecordReaderSuite.scala b/core/src/test/scala/org/apache/spark/input/WholeTextFileRecordReaderSuite.scala
index 24184b02cb..d852255a4f 100644
--- a/core/src/test/scala/org/apache/spark/input/WholeTextFileRecordReaderSuite.scala
+++ b/core/src/test/scala/org/apache/spark/input/WholeTextFileRecordReaderSuite.scala
@@ -23,13 +23,12 @@ import java.io.FileOutputStream
 
 import scala.collection.immutable.IndexedSeq
 
-import org.scalatest.BeforeAndAfterAll
-
 import org.apache.hadoop.io.Text
+import org.apache.hadoop.io.compress.{CompressionCodecFactory, DefaultCodec, GzipCodec}
+import org.scalatest.BeforeAndAfterAll
 
 import org.apache.spark.{Logging, SparkConf, SparkContext, SparkFunSuite}
 import org.apache.spark.util.Utils
-import org.apache.hadoop.io.compress.{DefaultCodec, CompressionCodecFactory, GzipCodec}
 
 /**
  * Tests the correctness of
diff --git a/core/src/test/scala/org/apache/spark/memory/MemoryManagerSuite.scala b/core/src/test/scala/org/apache/spark/memory/MemoryManagerSuite.scala
index 555b640cb4..f2924a6a5c 100644
--- a/core/src/test/scala/org/apache/spark/memory/MemoryManagerSuite.scala
+++ b/core/src/test/scala/org/apache/spark/memory/MemoryManagerSuite.scala
@@ -20,8 +20,8 @@ package org.apache.spark.memory
 import java.util.concurrent.atomic.AtomicLong
 
 import scala.collection.mutable
-import scala.concurrent.duration.Duration
 import scala.concurrent.{Await, ExecutionContext, Future}
+import scala.concurrent.duration.Duration
 
 import org.mockito.Matchers.{any, anyLong}
 import org.mockito.Mockito.{mock, when, RETURNS_SMART_NULLS}
diff --git a/core/src/test/scala/org/apache/spark/memory/MemoryTestingUtils.scala b/core/src/test/scala/org/apache/spark/memory/MemoryTestingUtils.scala
index 4b4c3b0311..0e60cc8e77 100644
--- a/core/src/test/scala/org/apache/spark/memory/MemoryTestingUtils.scala
+++ b/core/src/test/scala/org/apache/spark/memory/MemoryTestingUtils.scala
@@ -17,7 +17,7 @@
 
 package org.apache.spark.memory
 
-import org.apache.spark.{SparkEnv, TaskContextImpl, TaskContext}
+import org.apache.spark.{SparkEnv, TaskContext, TaskContextImpl}
 
 /**
  * Helper methods for mocking out memory-management-related classes in tests.
diff --git a/core/src/test/scala/org/apache/spark/memory/TestMemoryManager.scala b/core/src/test/scala/org/apache/spark/memory/TestMemoryManager.scala
index 0706a6e45d..4a1e49b45d 100644
--- a/core/src/test/scala/org/apache/spark/memory/TestMemoryManager.scala
+++ b/core/src/test/scala/org/apache/spark/memory/TestMemoryManager.scala
@@ -20,7 +20,7 @@ package org.apache.spark.memory
 import scala.collection.mutable
 
 import org.apache.spark.SparkConf
-import org.apache.spark.storage.{BlockStatus, BlockId}
+import org.apache.spark.storage.{BlockId, BlockStatus}
 
 class TestMemoryManager(conf: SparkConf)
   extends MemoryManager(conf, numCores = 1, Long.MaxValue, Long.MaxValue) {
diff --git a/core/src/test/scala/org/apache/spark/metrics/InputOutputMetricsSuite.scala b/core/src/test/scala/org/apache/spark/metrics/InputOutputMetricsSuite.scala
index 44eb5a0469..aaf62e0f91 100644
--- a/core/src/test/scala/org/apache/spark/metrics/InputOutputMetricsSuite.scala
+++ b/core/src/test/scala/org/apache/spark/metrics/InputOutputMetricsSuite.scala
@@ -25,17 +25,17 @@ import org.apache.commons.lang3.RandomUtils
 import org.apache.hadoop.conf.Configuration
 import org.apache.hadoop.fs.{FileSystem, Path}
 import org.apache.hadoop.io.{LongWritable, Text}
+import org.apache.hadoop.mapred.{FileSplit => OldFileSplit, InputSplit => OldInputSplit,
+  JobConf, LineRecordReader => OldLineRecordReader, RecordReader => OldRecordReader,
+  Reporter, TextInputFormat => OldTextInputFormat}
 import org.apache.hadoop.mapred.lib.{CombineFileInputFormat => OldCombineFileInputFormat,
   CombineFileRecordReader => OldCombineFileRecordReader, CombineFileSplit => OldCombineFileSplit}
-import org.apache.hadoop.mapred.{JobConf, Reporter, FileSplit => OldFileSplit,
-  InputSplit => OldInputSplit, LineRecordReader => OldLineRecordReader,
-  RecordReader => OldRecordReader, TextInputFormat => OldTextInputFormat}
+import org.apache.hadoop.mapreduce.{InputSplit => NewInputSplit, RecordReader => NewRecordReader,
+  TaskAttemptContext}
 import org.apache.hadoop.mapreduce.lib.input.{CombineFileInputFormat => NewCombineFileInputFormat,
   CombineFileRecordReader => NewCombineFileRecordReader, CombineFileSplit => NewCombineFileSplit,
   FileSplit => NewFileSplit, TextInputFormat => NewTextInputFormat}
 import org.apache.hadoop.mapreduce.lib.output.{TextOutputFormat => NewTextOutputFormat}
-import org.apache.hadoop.mapreduce.{TaskAttemptContext, InputSplit => NewInputSplit,
-  RecordReader => NewRecordReader}
 import org.scalatest.BeforeAndAfter
 
 import org.apache.spark.{SharedSparkContext, SparkFunSuite}
diff --git a/core/src/test/scala/org/apache/spark/metrics/MetricsConfigSuite.scala b/core/src/test/scala/org/apache/spark/metrics/MetricsConfigSuite.scala
index 41f2ff725a..b24f5d732f 100644
--- a/core/src/test/scala/org/apache/spark/metrics/MetricsConfigSuite.scala
+++ b/core/src/test/scala/org/apache/spark/metrics/MetricsConfigSuite.scala
@@ -17,10 +17,9 @@
 
 package org.apache.spark.metrics
 
-import org.apache.spark.SparkConf
-
 import org.scalatest.BeforeAndAfter
 
+import org.apache.spark.SparkConf
 import org.apache.spark.SparkFunSuite
 
 class MetricsConfigSuite extends SparkFunSuite with BeforeAndAfter {
diff --git a/core/src/test/scala/org/apache/spark/metrics/MetricsSystemSuite.scala b/core/src/test/scala/org/apache/spark/metrics/MetricsSystemSuite.scala
index 9c389c76bf..5d8554229d 100644
--- a/core/src/test/scala/org/apache/spark/metrics/MetricsSystemSuite.scala
+++ b/core/src/test/scala/org/apache/spark/metrics/MetricsSystemSuite.scala
@@ -17,16 +17,15 @@
 
 package org.apache.spark.metrics
 
+import scala.collection.mutable.ArrayBuffer
+
+import com.codahale.metrics.MetricRegistry
 import org.scalatest.{BeforeAndAfter, PrivateMethodTester}
 
 import org.apache.spark.{SecurityManager, SparkConf, SparkFunSuite}
 import org.apache.spark.deploy.master.MasterSource
 import org.apache.spark.metrics.source.Source
 
-import com.codahale.metrics.MetricRegistry
-
-import scala.collection.mutable.ArrayBuffer
-
 class MetricsSystemSuite extends SparkFunSuite with BeforeAndAfter with PrivateMethodTester{
   var filePath: String = _
   var conf: SparkConf = null
diff --git a/core/src/test/scala/org/apache/spark/network/netty/NettyBlockTransferSecuritySuite.scala b/core/src/test/scala/org/apache/spark/network/netty/NettyBlockTransferSecuritySuite.scala
index 98da94139f..47dbcb8fc0 100644
--- a/core/src/test/scala/org/apache/spark/network/netty/NettyBlockTransferSecuritySuite.scala
+++ b/core/src/test/scala/org/apache/spark/network/netty/NettyBlockTransferSecuritySuite.scala
@@ -22,20 +22,21 @@ import java.nio._
 import java.nio.charset.Charset
 import java.util.concurrent.TimeUnit
 
-import scala.concurrent.duration._
 import scala.concurrent.{Await, Promise}
+import scala.concurrent.duration._
 import scala.util.{Failure, Success, Try}
 
 import com.google.common.io.CharStreams
-import org.apache.spark.network.buffer.{ManagedBuffer, NioManagedBuffer}
-import org.apache.spark.network.shuffle.BlockFetchingListener
-import org.apache.spark.network.{BlockDataManager, BlockTransferService}
-import org.apache.spark.storage.{BlockId, ShuffleBlockId}
-import org.apache.spark.{SecurityManager, SparkConf, SparkFunSuite}
 import org.mockito.Mockito._
 import org.scalatest.mock.MockitoSugar
 import org.scalatest.ShouldMatchers
 
+import org.apache.spark.{SecurityManager, SparkConf, SparkFunSuite}
+import org.apache.spark.network.{BlockDataManager, BlockTransferService}
+import org.apache.spark.network.buffer.{ManagedBuffer, NioManagedBuffer}
+import org.apache.spark.network.shuffle.BlockFetchingListener
+import org.apache.spark.storage.{BlockId, ShuffleBlockId}
+
 class NettyBlockTransferSecuritySuite extends SparkFunSuite with MockitoSugar with ShouldMatchers {
   test("security default off") {
     val conf = new SparkConf()
diff --git a/core/src/test/scala/org/apache/spark/network/netty/NettyBlockTransferServiceSuite.scala b/core/src/test/scala/org/apache/spark/network/netty/NettyBlockTransferServiceSuite.scala
index 92daf4e6a2..cc1a9e0287 100644
--- a/core/src/test/scala/org/apache/spark/network/netty/NettyBlockTransferServiceSuite.scala
+++ b/core/src/test/scala/org/apache/spark/network/netty/NettyBlockTransferServiceSuite.scala
@@ -17,11 +17,12 @@
 
 package org.apache.spark.network.netty
 
-import org.apache.spark.network.BlockDataManager
-import org.apache.spark.{SecurityManager, SparkConf, SparkFunSuite}
 import org.mockito.Mockito.mock
 import org.scalatest._
 
+import org.apache.spark.{SecurityManager, SparkConf, SparkFunSuite}
+import org.apache.spark.network.BlockDataManager
+
 class NettyBlockTransferServiceSuite
   extends SparkFunSuite
   with BeforeAndAfterEach
diff --git a/core/src/test/scala/org/apache/spark/rdd/LocalCheckpointSuite.scala b/core/src/test/scala/org/apache/spark/rdd/LocalCheckpointSuite.scala
index 3a22a9850a..e694f5e5e7 100644
--- a/core/src/test/scala/org/apache/spark/rdd/LocalCheckpointSuite.scala
+++ b/core/src/test/scala/org/apache/spark/rdd/LocalCheckpointSuite.scala
@@ -17,9 +17,9 @@
 
 package org.apache.spark.rdd
 
-import org.apache.spark.{SparkException, SparkContext, LocalSparkContext, SparkFunSuite}
-
 import org.mockito.Mockito.spy
+
+import org.apache.spark.{LocalSparkContext, SparkContext, SparkException, SparkFunSuite}
 import org.apache.spark.storage.{RDDBlockId, StorageLevel}
 
 /**
diff --git a/core/src/test/scala/org/apache/spark/rdd/PairRDDFunctionsSuite.scala b/core/src/test/scala/org/apache/spark/rdd/PairRDDFunctionsSuite.scala
index 7d2cfcca94..16e2d2e636 100644
--- a/core/src/test/scala/org/apache/spark/rdd/PairRDDFunctionsSuite.scala
+++ b/core/src/test/scala/org/apache/spark/rdd/PairRDDFunctionsSuite.scala
@@ -17,18 +17,18 @@
 
 package org.apache.spark.rdd
 
-import org.apache.commons.math3.distribution.{PoissonDistribution, BinomialDistribution}
-import org.apache.hadoop.fs.FileSystem
-import org.apache.hadoop.mapred._
-import org.apache.hadoop.util.Progressable
-
 import scala.collection.mutable.{ArrayBuffer, HashSet}
 import scala.util.Random
 
+import org.apache.commons.math3.distribution.{BinomialDistribution, PoissonDistribution}
 import org.apache.hadoop.conf.{Configurable, Configuration}
-import org.apache.hadoop.mapreduce.{JobContext => NewJobContext, OutputCommitter => NewOutputCommitter,
-OutputFormat => NewOutputFormat, RecordWriter => NewRecordWriter,
-TaskAttemptContext => NewTaskAttempContext}
+import org.apache.hadoop.fs.FileSystem
+import org.apache.hadoop.mapred._
+import org.apache.hadoop.mapreduce.{JobContext => NewJobContext,
+  OutputCommitter => NewOutputCommitter, OutputFormat => NewOutputFormat,
+  RecordWriter => NewRecordWriter, TaskAttemptContext => NewTaskAttempContext}
+import org.apache.hadoop.util.Progressable
+
 import org.apache.spark.{Partitioner, SharedSparkContext, SparkFunSuite}
 import org.apache.spark.util.Utils
 
diff --git a/core/src/test/scala/org/apache/spark/rdd/PipedRDDSuite.scala b/core/src/test/scala/org/apache/spark/rdd/PipedRDDSuite.scala
index 5f73ec8675..1eebc924a5 100644
--- a/core/src/test/scala/org/apache/spark/rdd/PipedRDDSuite.scala
+++ b/core/src/test/scala/org/apache/spark/rdd/PipedRDDSuite.scala
@@ -19,15 +19,15 @@ package org.apache.spark.rdd
 
 import java.io.File
 
-import org.apache.hadoop.fs.Path
-import org.apache.hadoop.io.{LongWritable, Text}
-import org.apache.hadoop.mapred.{FileSplit, JobConf, TextInputFormat}
-
 import scala.collection.Map
 import scala.language.postfixOps
 import scala.sys.process._
 import scala.util.Try
 
+import org.apache.hadoop.fs.Path
+import org.apache.hadoop.io.{LongWritable, Text}
+import org.apache.hadoop.mapred.{FileSplit, JobConf, TextInputFormat}
+
 import org.apache.spark._
 import org.apache.spark.util.Utils
 
diff --git a/core/src/test/scala/org/apache/spark/rdd/RDDSuite.scala b/core/src/test/scala/org/apache/spark/rdd/RDDSuite.scala
index 18d1466bb7..24acbed4d7 100644
--- a/core/src/test/scala/org/apache/spark/rdd/RDDSuite.scala
+++ b/core/src/test/scala/org/apache/spark/rdd/RDDSuite.scala
@@ -17,14 +17,14 @@
 
 package org.apache.spark.rdd
 
-import java.io.{ObjectInputStream, ObjectOutputStream, IOException}
+import java.io.{IOException, ObjectInputStream, ObjectOutputStream}
 
-import com.esotericsoftware.kryo.KryoException
-
-import scala.collection.mutable.{ArrayBuffer, HashMap}
 import scala.collection.JavaConverters._
+import scala.collection.mutable.{ArrayBuffer, HashMap}
 import scala.reflect.ClassTag
 
+import com.esotericsoftware.kryo.KryoException
+
 import org.apache.spark._
 import org.apache.spark.api.java.{JavaRDD, JavaSparkContext}
 import org.apache.spark.rdd.RDDSuiteUtils._
diff --git a/core/src/test/scala/org/apache/spark/rpc/RpcEnvSuite.scala b/core/src/test/scala/org/apache/spark/rpc/RpcEnvSuite.scala
index 924fce7f61..64e486d791 100644
--- a/core/src/test/scala/org/apache/spark/rpc/RpcEnvSuite.scala
+++ b/core/src/test/scala/org/apache/spark/rpc/RpcEnvSuite.scala
@@ -18,9 +18,9 @@
 package org.apache.spark.rpc
 
 import java.io.{File, NotSerializableException}
-import java.util.UUID
 import java.nio.charset.StandardCharsets.UTF_8
-import java.util.concurrent.{TimeUnit, CountDownLatch, TimeoutException}
+import java.util.UUID
+import java.util.concurrent.{CountDownLatch, TimeoutException, TimeUnit}
 
 import scala.collection.mutable
 import scala.concurrent.Await
diff --git a/core/src/test/scala/org/apache/spark/rpc/netty/InboxSuite.scala b/core/src/test/scala/org/apache/spark/rpc/netty/InboxSuite.scala
index 2136795b18..12113be75c 100644
--- a/core/src/test/scala/org/apache/spark/rpc/netty/InboxSuite.scala
+++ b/core/src/test/scala/org/apache/spark/rpc/netty/InboxSuite.scala
@@ -23,7 +23,7 @@ import java.util.concurrent.atomic.AtomicInteger
 import org.mockito.Mockito._
 
 import org.apache.spark.SparkFunSuite
-import org.apache.spark.rpc.{RpcEnv, RpcEndpoint, RpcAddress, TestRpcEndpoint}
+import org.apache.spark.rpc.{RpcAddress, RpcEndpoint, RpcEnv, TestRpcEndpoint}
 
 class InboxSuite extends SparkFunSuite {
 
diff --git a/core/src/test/scala/org/apache/spark/rpc/netty/NettyRpcHandlerSuite.scala b/core/src/test/scala/org/apache/spark/rpc/netty/NettyRpcHandlerSuite.scala
index d4aebe9fd9..0c156fef0a 100644
--- a/core/src/test/scala/org/apache/spark/rpc/netty/NettyRpcHandlerSuite.scala
+++ b/core/src/test/scala/org/apache/spark/rpc/netty/NettyRpcHandlerSuite.scala
@@ -21,11 +21,11 @@ import java.net.InetSocketAddress
 import java.nio.ByteBuffer
 
 import io.netty.channel.Channel
-import org.mockito.Mockito._
 import org.mockito.Matchers._
+import org.mockito.Mockito._
 
 import org.apache.spark.SparkFunSuite
-import org.apache.spark.network.client.{TransportResponseHandler, TransportClient}
+import org.apache.spark.network.client.{TransportClient, TransportResponseHandler}
 import org.apache.spark.network.server.StreamManager
 import org.apache.spark.rpc._
 
diff --git a/core/src/test/scala/org/apache/spark/scheduler/CoarseGrainedSchedulerBackendSuite.scala b/core/src/test/scala/org/apache/spark/scheduler/CoarseGrainedSchedulerBackendSuite.scala
index eef6aafa62..70f40fb26c 100644
--- a/core/src/test/scala/org/apache/spark/scheduler/CoarseGrainedSchedulerBackendSuite.scala
+++ b/core/src/test/scala/org/apache/spark/scheduler/CoarseGrainedSchedulerBackendSuite.scala
@@ -18,7 +18,7 @@
 package org.apache.spark.scheduler
 
 import org.apache.spark.{LocalSparkContext, SparkConf, SparkContext, SparkException, SparkFunSuite}
-import org.apache.spark.util.{SerializableBuffer, AkkaUtils}
+import org.apache.spark.util.{AkkaUtils, SerializableBuffer}
 
 class CoarseGrainedSchedulerBackendSuite extends SparkFunSuite with LocalSparkContext {
 
diff --git a/core/src/test/scala/org/apache/spark/scheduler/DAGSchedulerSuite.scala b/core/src/test/scala/org/apache/spark/scheduler/DAGSchedulerSuite.scala
index 2869f0fde4..370a284d29 100644
--- a/core/src/test/scala/org/apache/spark/scheduler/DAGSchedulerSuite.scala
+++ b/core/src/test/scala/org/apache/spark/scheduler/DAGSchedulerSuite.scala
@@ -19,7 +19,7 @@ package org.apache.spark.scheduler
 
 import java.util.Properties
 
-import scala.collection.mutable.{ArrayBuffer, HashSet, HashMap, Map}
+import scala.collection.mutable.{ArrayBuffer, HashMap, HashSet, Map}
 import scala.language.reflectiveCalls
 import scala.util.control.NonFatal
 
diff --git a/core/src/test/scala/org/apache/spark/scheduler/MapStatusSuite.scala b/core/src/test/scala/org/apache/spark/scheduler/MapStatusSuite.scala
index 15c8de61b8..56e0f01b3b 100644
--- a/core/src/test/scala/org/apache/spark/scheduler/MapStatusSuite.scala
+++ b/core/src/test/scala/org/apache/spark/scheduler/MapStatusSuite.scala
@@ -17,13 +17,13 @@
 
 package org.apache.spark.scheduler
 
-import org.apache.spark.storage.BlockManagerId
+import scala.util.Random
 
-import org.apache.spark.{SparkConf, SparkFunSuite}
-import org.apache.spark.serializer.JavaSerializer
 import org.roaringbitmap.RoaringBitmap
 
-import scala.util.Random
+import org.apache.spark.{SparkConf, SparkFunSuite}
+import org.apache.spark.serializer.JavaSerializer
+import org.apache.spark.storage.BlockManagerId
 
 class MapStatusSuite extends SparkFunSuite {
 
diff --git a/core/src/test/scala/org/apache/spark/scheduler/NotSerializableFakeTask.scala b/core/src/test/scala/org/apache/spark/scheduler/NotSerializableFakeTask.scala
index f333247924..1dca4bd89f 100644
--- a/core/src/test/scala/org/apache/spark/scheduler/NotSerializableFakeTask.scala
+++ b/core/src/test/scala/org/apache/spark/scheduler/NotSerializableFakeTask.scala
@@ -17,7 +17,7 @@
 
 package org.apache.spark.scheduler
 
-import java.io.{ObjectInputStream, ObjectOutputStream, IOException}
+import java.io.{IOException, ObjectInputStream, ObjectOutputStream}
 
 import org.apache.spark.TaskContext
 
diff --git a/core/src/test/scala/org/apache/spark/scheduler/OutputCommitCoordinatorIntegrationSuite.scala b/core/src/test/scala/org/apache/spark/scheduler/OutputCommitCoordinatorIntegrationSuite.scala
index 1ae5b030f0..9f41aca8a1 100644
--- a/core/src/test/scala/org/apache/spark/scheduler/OutputCommitCoordinatorIntegrationSuite.scala
+++ b/core/src/test/scala/org/apache/spark/scheduler/OutputCommitCoordinatorIntegrationSuite.scala
@@ -19,9 +19,9 @@ package org.apache.spark.scheduler
 
 import org.apache.hadoop.mapred.{FileOutputCommitter, TaskAttemptContext}
 import org.scalatest.concurrent.Timeouts
-import org.scalatest.time.{Span, Seconds}
+import org.scalatest.time.{Seconds, Span}
 
-import org.apache.spark.{SparkConf, SparkContext, LocalSparkContext, SparkFunSuite, TaskContext}
+import org.apache.spark.{LocalSparkContext, SparkConf, SparkContext, SparkFunSuite, TaskContext}
 import org.apache.spark.util.Utils
 
 /**
diff --git a/core/src/test/scala/org/apache/spark/scheduler/OutputCommitCoordinatorSuite.scala b/core/src/test/scala/org/apache/spark/scheduler/OutputCommitCoordinatorSuite.scala
index 7345508bfe..c461da65bd 100644
--- a/core/src/test/scala/org/apache/spark/scheduler/OutputCommitCoordinatorSuite.scala
+++ b/core/src/test/scala/org/apache/spark/scheduler/OutputCommitCoordinatorSuite.scala
@@ -20,22 +20,21 @@ package org.apache.spark.scheduler
 import java.io.File
 import java.util.concurrent.TimeoutException
 
+import scala.concurrent.Await
+import scala.concurrent.duration._
+import scala.language.postfixOps
+
+import org.apache.hadoop.mapred.{JobConf, OutputCommitter, TaskAttemptContext, TaskAttemptID}
 import org.mockito.Matchers
 import org.mockito.Mockito._
 import org.mockito.invocation.InvocationOnMock
 import org.mockito.stubbing.Answer
 import org.scalatest.BeforeAndAfter
 
-import org.apache.hadoop.mapred.{TaskAttemptID, JobConf, TaskAttemptContext, OutputCommitter}
-
 import org.apache.spark._
-import org.apache.spark.rdd.{RDD, FakeOutputCommitter}
+import org.apache.spark.rdd.{FakeOutputCommitter, RDD}
 import org.apache.spark.util.Utils
 
-import scala.concurrent.Await
-import scala.concurrent.duration._
-import scala.language.postfixOps
-
 /**
  * Unit tests for the output commit coordination functionality.
  *
diff --git a/core/src/test/scala/org/apache/spark/scheduler/SparkListenerSuite.scala b/core/src/test/scala/org/apache/spark/scheduler/SparkListenerSuite.scala
index f20d5be7c0..dc15f5932d 100644
--- a/core/src/test/scala/org/apache/spark/scheduler/SparkListenerSuite.scala
+++ b/core/src/test/scala/org/apache/spark/scheduler/SparkListenerSuite.scala
@@ -24,10 +24,9 @@ import scala.collection.JavaConverters._
 
 import org.scalatest.Matchers
 
-import org.apache.spark.SparkException
+import org.apache.spark.{LocalSparkContext, SparkConf, SparkContext, SparkException, SparkFunSuite}
 import org.apache.spark.executor.TaskMetrics
 import org.apache.spark.util.ResetSystemProperties
-import org.apache.spark.{LocalSparkContext, SparkConf, SparkContext, SparkFunSuite}
 
 class SparkListenerSuite extends SparkFunSuite with LocalSparkContext with Matchers
   with ResetSystemProperties {
diff --git a/core/src/test/scala/org/apache/spark/scheduler/TaskContextSuite.scala b/core/src/test/scala/org/apache/spark/scheduler/TaskContextSuite.scala
index 40ebfdde92..e5ec44a9f3 100644
--- a/core/src/test/scala/org/apache/spark/scheduler/TaskContextSuite.scala
+++ b/core/src/test/scala/org/apache/spark/scheduler/TaskContextSuite.scala
@@ -17,17 +17,15 @@
 
 package org.apache.spark.scheduler
 
-import org.mockito.Mockito._
 import org.mockito.Matchers.any
-
+import org.mockito.Mockito._
 import org.scalatest.BeforeAndAfter
 
 import org.apache.spark._
+import org.apache.spark.metrics.source.JvmSource
 import org.apache.spark.network.util.JavaUtils
 import org.apache.spark.rdd.RDD
 import org.apache.spark.util.{TaskCompletionListener, TaskCompletionListenerException}
-import org.apache.spark.metrics.source.JvmSource
-
 
 class TaskContextSuite extends SparkFunSuite with BeforeAndAfter with LocalSparkContext {
 
diff --git a/core/src/test/scala/org/apache/spark/scheduler/cluster/mesos/CoarseMesosSchedulerBackendSuite.scala b/core/src/test/scala/org/apache/spark/scheduler/cluster/mesos/CoarseMesosSchedulerBackendSuite.scala
index 525ee0d3bd..a4110d2d46 100644
--- a/core/src/test/scala/org/apache/spark/scheduler/cluster/mesos/CoarseMesosSchedulerBackendSuite.scala
+++ b/core/src/test/scala/org/apache/spark/scheduler/cluster/mesos/CoarseMesosSchedulerBackendSuite.scala
@@ -20,17 +20,17 @@ package org.apache.spark.scheduler.cluster.mesos
 import java.util
 import java.util.Collections
 
-import org.apache.mesos.Protos.Value.Scalar
-import org.apache.mesos.Protos._
 import org.apache.mesos.{Protos, Scheduler, SchedulerDriver}
+import org.apache.mesos.Protos._
+import org.apache.mesos.Protos.Value.Scalar
+import org.mockito.Matchers
 import org.mockito.Matchers._
 import org.mockito.Mockito._
-import org.mockito.Matchers
 import org.scalatest.mock.MockitoSugar
 import org.scalatest.BeforeAndAfter
 
+import org.apache.spark.{LocalSparkContext, SecurityManager, SparkConf, SparkContext, SparkFunSuite}
 import org.apache.spark.scheduler.TaskSchedulerImpl
-import org.apache.spark.{LocalSparkContext, SparkConf, SparkContext, SecurityManager, SparkFunSuite}
 
 class CoarseMesosSchedulerBackendSuite extends SparkFunSuite
     with LocalSparkContext
diff --git a/core/src/test/scala/org/apache/spark/scheduler/cluster/mesos/MesosSchedulerBackendSuite.scala b/core/src/test/scala/org/apache/spark/scheduler/cluster/mesos/MesosSchedulerBackendSuite.scala
index c4dc560031..504e5780f3 100644
--- a/core/src/test/scala/org/apache/spark/scheduler/cluster/mesos/MesosSchedulerBackendSuite.scala
+++ b/core/src/test/scala/org/apache/spark/scheduler/cluster/mesos/MesosSchedulerBackendSuite.scala
@@ -26,19 +26,19 @@ import scala.collection.JavaConverters._
 import scala.collection.mutable
 import scala.collection.mutable.ArrayBuffer
 
-import org.apache.mesos.Protos.Value.Scalar
 import org.apache.mesos.Protos._
+import org.apache.mesos.Protos.Value.Scalar
 import org.apache.mesos.SchedulerDriver
+import org.mockito.{ArgumentCaptor, Matchers}
 import org.mockito.Matchers._
 import org.mockito.Mockito._
-import org.mockito.{ArgumentCaptor, Matchers}
 import org.scalatest.mock.MockitoSugar
 
+import org.apache.spark.{LocalSparkContext, SparkConf, SparkContext, SparkFunSuite}
 import org.apache.spark.executor.MesosExecutorBackend
-import org.apache.spark.scheduler.cluster.ExecutorInfo
 import org.apache.spark.scheduler.{LiveListenerBus, SparkListenerExecutorAdded,
   TaskDescription, TaskSchedulerImpl, WorkerOffer}
-import org.apache.spark.{LocalSparkContext, SparkConf, SparkContext, SparkFunSuite}
+import org.apache.spark.scheduler.cluster.ExecutorInfo
 
 class MesosSchedulerBackendSuite extends SparkFunSuite with LocalSparkContext with MockitoSugar {
 
diff --git a/core/src/test/scala/org/apache/spark/scheduler/mesos/MesosClusterSchedulerSuite.scala b/core/src/test/scala/org/apache/spark/scheduler/mesos/MesosClusterSchedulerSuite.scala
index f5cef1caaf..98fdc58786 100644
--- a/core/src/test/scala/org/apache/spark/scheduler/mesos/MesosClusterSchedulerSuite.scala
+++ b/core/src/test/scala/org/apache/spark/scheduler/mesos/MesosClusterSchedulerSuite.scala
@@ -21,11 +21,10 @@ import java.util.Date
 
 import org.scalatest.mock.MockitoSugar
 
+import org.apache.spark.{LocalSparkContext, SparkConf, SparkFunSuite}
 import org.apache.spark.deploy.Command
 import org.apache.spark.deploy.mesos.MesosDriverDescription
 import org.apache.spark.scheduler.cluster.mesos._
-import org.apache.spark.{LocalSparkContext, SparkConf, SparkFunSuite}
-
 
 class MesosClusterSchedulerSuite extends SparkFunSuite with LocalSparkContext with MockitoSugar {
 
diff --git a/core/src/test/scala/org/apache/spark/serializer/GenericAvroSerializerSuite.scala b/core/src/test/scala/org/apache/spark/serializer/GenericAvroSerializerSuite.scala
index 87f25e7245..3734f1cb40 100644
--- a/core/src/test/scala/org/apache/spark/serializer/GenericAvroSerializerSuite.scala
+++ b/core/src/test/scala/org/apache/spark/serializer/GenericAvroSerializerSuite.scala
@@ -20,11 +20,11 @@ package org.apache.spark.serializer
 import java.io.{ByteArrayInputStream, ByteArrayOutputStream}
 import java.nio.ByteBuffer
 
-import com.esotericsoftware.kryo.io.{Output, Input}
-import org.apache.avro.{SchemaBuilder, Schema}
+import com.esotericsoftware.kryo.io.{Input, Output}
+import org.apache.avro.{Schema, SchemaBuilder}
 import org.apache.avro.generic.GenericData.Record
 
-import org.apache.spark.{SparkFunSuite, SharedSparkContext}
+import org.apache.spark.{SharedSparkContext, SparkFunSuite}
 
 class GenericAvroSerializerSuite extends SparkFunSuite with SharedSparkContext {
   conf.set("spark.serializer", "org.apache.spark.serializer.KryoSerializer")
diff --git a/core/src/test/scala/org/apache/spark/serializer/KryoSerializerDistributedSuite.scala b/core/src/test/scala/org/apache/spark/serializer/KryoSerializerDistributedSuite.scala
index 935a091f14..a0483f6483 100644
--- a/core/src/test/scala/org/apache/spark/serializer/KryoSerializerDistributedSuite.scala
+++ b/core/src/test/scala/org/apache/spark/serializer/KryoSerializerDistributedSuite.scala
@@ -17,12 +17,11 @@
 
 package org.apache.spark.serializer
 
-import org.apache.spark.util.Utils
-
 import com.esotericsoftware.kryo.Kryo
 
 import org.apache.spark._
 import org.apache.spark.serializer.KryoDistributedTest._
+import org.apache.spark.util.Utils
 
 class KryoSerializerDistributedSuite extends SparkFunSuite {
 
diff --git a/core/src/test/scala/org/apache/spark/serializer/KryoSerializerResizableOutputSuite.scala b/core/src/test/scala/org/apache/spark/serializer/KryoSerializerResizableOutputSuite.scala
index a9b209ccfc..21251f0b93 100644
--- a/core/src/test/scala/org/apache/spark/serializer/KryoSerializerResizableOutputSuite.scala
+++ b/core/src/test/scala/org/apache/spark/serializer/KryoSerializerResizableOutputSuite.scala
@@ -18,11 +18,10 @@
 package org.apache.spark.serializer
 
 import org.apache.spark.{SparkConf, SparkFunSuite}
-import org.apache.spark.SparkContext
 import org.apache.spark.LocalSparkContext
+import org.apache.spark.SparkContext
 import org.apache.spark.SparkException
 
-
 class KryoSerializerResizableOutputSuite extends SparkFunSuite {
 
   // trial and error showed this will not serialize with 1mb buffer
diff --git a/core/src/test/scala/org/apache/spark/serializer/KryoSerializerSuite.scala b/core/src/test/scala/org/apache/spark/serializer/KryoSerializerSuite.scala
index 9fcc22b608..8f9b453a6e 100644
--- a/core/src/test/scala/org/apache/spark/serializer/KryoSerializerSuite.scala
+++ b/core/src/test/scala/org/apache/spark/serializer/KryoSerializerSuite.scala
@@ -17,7 +17,7 @@
 
 package org.apache.spark.serializer
 
-import java.io.{ByteArrayInputStream, ByteArrayOutputStream, FileOutputStream, FileInputStream}
+import java.io.{ByteArrayInputStream, ByteArrayOutputStream, FileInputStream, FileOutputStream}
 
 import scala.collection.JavaConverters._
 import scala.collection.mutable
@@ -25,14 +25,13 @@ import scala.reflect.ClassTag
 
 import com.esotericsoftware.kryo.Kryo
 import com.esotericsoftware.kryo.io.{Input => KryoInput, Output => KryoOutput}
-
 import org.roaringbitmap.RoaringBitmap
 
 import org.apache.spark.{SharedSparkContext, SparkConf, SparkFunSuite}
 import org.apache.spark.scheduler.HighlyCompressedMapStatus
 import org.apache.spark.serializer.KryoTest._
-import org.apache.spark.util.Utils
 import org.apache.spark.storage.BlockManagerId
+import org.apache.spark.util.Utils
 
 class KryoSerializerSuite extends SparkFunSuite with SharedSparkContext {
   conf.set("spark.serializer", "org.apache.spark.serializer.KryoSerializer")
diff --git a/core/src/test/scala/org/apache/spark/serializer/TestSerializer.scala b/core/src/test/scala/org/apache/spark/serializer/TestSerializer.scala
index c1e0a29a34..17037870f7 100644
--- a/core/src/test/scala/org/apache/spark/serializer/TestSerializer.scala
+++ b/core/src/test/scala/org/apache/spark/serializer/TestSerializer.scala
@@ -17,12 +17,11 @@
 
 package org.apache.spark.serializer
 
-import java.io.{EOFException, OutputStream, InputStream}
+import java.io.{EOFException, InputStream, OutputStream}
 import java.nio.ByteBuffer
 
 import scala.reflect.ClassTag
 
-
 /**
  * A serializer implementation that always returns two elements in a deserialization stream.
  */
diff --git a/core/src/test/scala/org/apache/spark/shuffle/sort/BypassMergeSortShuffleWriterSuite.scala b/core/src/test/scala/org/apache/spark/shuffle/sort/BypassMergeSortShuffleWriterSuite.scala
index bb331bb385..e33408b94e 100644
--- a/core/src/test/scala/org/apache/spark/shuffle/sort/BypassMergeSortShuffleWriterSuite.scala
+++ b/core/src/test/scala/org/apache/spark/shuffle/sort/BypassMergeSortShuffleWriterSuite.scala
@@ -23,8 +23,8 @@ import java.util.UUID
 import scala.collection.mutable
 import scala.collection.mutable.ArrayBuffer
 
-import org.mockito.Answers.RETURNS_SMART_NULLS
 import org.mockito.{Mock, MockitoAnnotations}
+import org.mockito.Answers.RETURNS_SMART_NULLS
 import org.mockito.Matchers._
 import org.mockito.Mockito._
 import org.mockito.invocation.InvocationOnMock
@@ -32,9 +32,9 @@ import org.mockito.stubbing.Answer
 import org.scalatest.BeforeAndAfterEach
 
 import org.apache.spark._
-import org.apache.spark.executor.{TaskMetrics, ShuffleWriteMetrics}
-import org.apache.spark.shuffle.IndexShuffleBlockResolver
+import org.apache.spark.executor.{ShuffleWriteMetrics, TaskMetrics}
 import org.apache.spark.serializer.{JavaSerializer, SerializerInstance}
+import org.apache.spark.shuffle.IndexShuffleBlockResolver
 import org.apache.spark.storage._
 import org.apache.spark.util.Utils
 
diff --git a/core/src/test/scala/org/apache/spark/storage/BlockManagerReplicationSuite.scala b/core/src/test/scala/org/apache/spark/storage/BlockManagerReplicationSuite.scala
index 6e3f500e15..3fd6fb4560 100644
--- a/core/src/test/scala/org/apache/spark/storage/BlockManagerReplicationSuite.scala
+++ b/core/src/test/scala/org/apache/spark/storage/BlockManagerReplicationSuite.scala
@@ -26,11 +26,11 @@ import org.mockito.Mockito.{mock, when}
 import org.scalatest.{BeforeAndAfter, Matchers}
 import org.scalatest.concurrent.Eventually._
 
-import org.apache.spark.network.netty.NettyBlockTransferService
-import org.apache.spark.rpc.RpcEnv
 import org.apache.spark._
 import org.apache.spark.memory.StaticMemoryManager
 import org.apache.spark.network.BlockTransferService
+import org.apache.spark.network.netty.NettyBlockTransferService
+import org.apache.spark.rpc.RpcEnv
 import org.apache.spark.scheduler.LiveListenerBus
 import org.apache.spark.serializer.KryoSerializer
 import org.apache.spark.shuffle.hash.HashShuffleManager
diff --git a/core/src/test/scala/org/apache/spark/storage/BlockManagerSuite.scala b/core/src/test/scala/org/apache/spark/storage/BlockManagerSuite.scala
index 2224a444c7..21db3b1c9f 100644
--- a/core/src/test/scala/org/apache/spark/storage/BlockManagerSuite.scala
+++ b/core/src/test/scala/org/apache/spark/storage/BlockManagerSuite.scala
@@ -25,24 +25,23 @@ import scala.concurrent.duration._
 import scala.language.implicitConversions
 import scala.language.postfixOps
 
-import org.mockito.Mockito.{mock, when}
 import org.mockito.{Matchers => mc}
+import org.mockito.Mockito.{mock, when}
 import org.scalatest._
 import org.scalatest.concurrent.Eventually._
 import org.scalatest.concurrent.Timeouts._
 
-import org.apache.spark.network.netty.NettyBlockTransferService
-import org.apache.spark.rpc.RpcEnv
 import org.apache.spark._
 import org.apache.spark.executor.DataReadMethod
 import org.apache.spark.memory.StaticMemoryManager
+import org.apache.spark.network.netty.NettyBlockTransferService
+import org.apache.spark.rpc.RpcEnv
 import org.apache.spark.scheduler.LiveListenerBus
 import org.apache.spark.serializer.{JavaSerializer, KryoSerializer}
 import org.apache.spark.shuffle.hash.HashShuffleManager
 import org.apache.spark.storage.BlockManagerMessages.BlockManagerHeartbeat
 import org.apache.spark.util._
 
-
 class BlockManagerSuite extends SparkFunSuite with Matchers with BeforeAndAfterEach
   with PrivateMethodTester with ResetSystemProperties {
 
diff --git a/core/src/test/scala/org/apache/spark/storage/LocalDirsSuite.scala b/core/src/test/scala/org/apache/spark/storage/LocalDirsSuite.scala
index cc50289c7b..c7074078d8 100644
--- a/core/src/test/scala/org/apache/spark/storage/LocalDirsSuite.scala
+++ b/core/src/test/scala/org/apache/spark/storage/LocalDirsSuite.scala
@@ -19,11 +19,10 @@ package org.apache.spark.storage
 
 import java.io.File
 
-import org.apache.spark.util.Utils
 import org.scalatest.BeforeAndAfter
 
 import org.apache.spark.{SparkConf, SparkFunSuite}
-import org.apache.spark.util.SparkConfWithEnv
+import org.apache.spark.util.{SparkConfWithEnv, Utils}
 
 /**
  * Tests for the spark.local.dir and SPARK_LOCAL_DIRS configuration options.
diff --git a/core/src/test/scala/org/apache/spark/ui/UISeleniumSuite.scala b/core/src/test/scala/org/apache/spark/ui/UISeleniumSuite.scala
index 0e36d7fda4..aa22f3ba2b 100644
--- a/core/src/test/scala/org/apache/spark/ui/UISeleniumSuite.scala
+++ b/core/src/test/scala/org/apache/spark/ui/UISeleniumSuite.scala
@@ -18,7 +18,7 @@
 package org.apache.spark.ui
 
 import java.net.{HttpURLConnection, URL}
-import javax.servlet.http.{HttpServletResponse, HttpServletRequest}
+import javax.servlet.http.{HttpServletRequest, HttpServletResponse}
 
 import scala.io.Source
 import scala.xml.Node
@@ -26,16 +26,16 @@ import scala.xml.Node
 import com.gargoylesoftware.htmlunit.DefaultCssErrorHandler
 import org.json4s._
 import org.json4s.jackson.JsonMethods
-import org.openqa.selenium.htmlunit.HtmlUnitDriver
 import org.openqa.selenium.{By, WebDriver}
+import org.openqa.selenium.htmlunit.HtmlUnitDriver
 import org.scalatest._
 import org.scalatest.concurrent.Eventually._
 import org.scalatest.selenium.WebBrowser
 import org.scalatest.time.SpanSugar._
 import org.w3c.css.sac.CSSParseException
 
-import org.apache.spark.LocalSparkContext._
 import org.apache.spark._
+import org.apache.spark.LocalSparkContext._
 import org.apache.spark.api.java.StorageLevels
 import org.apache.spark.deploy.history.HistoryServerSuite
 import org.apache.spark.shuffle.FetchFailedException
diff --git a/core/src/test/scala/org/apache/spark/ui/UISuite.scala b/core/src/test/scala/org/apache/spark/ui/UISuite.scala
index 8f9502b567..2d28b67ef2 100644
--- a/core/src/test/scala/org/apache/spark/ui/UISuite.scala
+++ b/core/src/test/scala/org/apache/spark/ui/UISuite.scala
@@ -26,8 +26,8 @@ import org.eclipse.jetty.servlet.ServletContextHandler
 import org.scalatest.concurrent.Eventually._
 import org.scalatest.time.SpanSugar._
 
-import org.apache.spark.LocalSparkContext._
 import org.apache.spark.{SparkConf, SparkContext, SparkFunSuite}
+import org.apache.spark.LocalSparkContext._
 
 class UISuite extends SparkFunSuite {
 
diff --git a/core/src/test/scala/org/apache/spark/ui/scope/RDDOperationGraphListenerSuite.scala b/core/src/test/scala/org/apache/spark/ui/scope/RDDOperationGraphListenerSuite.scala
index 86b0788518..3fb78da0c7 100644
--- a/core/src/test/scala/org/apache/spark/ui/scope/RDDOperationGraphListenerSuite.scala
+++ b/core/src/test/scala/org/apache/spark/ui/scope/RDDOperationGraphListenerSuite.scala
@@ -19,9 +19,6 @@ package org.apache.spark.ui.scope
 
 import org.apache.spark.{SparkConf, SparkFunSuite}
 import org.apache.spark.scheduler._
-import org.apache.spark.scheduler.SparkListenerStageSubmitted
-import org.apache.spark.scheduler.SparkListenerStageCompleted
-import org.apache.spark.scheduler.SparkListenerJobStart
 
 /**
  * Tests that this listener populates and cleans up its data structures properly.
diff --git a/core/src/test/scala/org/apache/spark/ui/storage/StorageTabSuite.scala b/core/src/test/scala/org/apache/spark/ui/storage/StorageTabSuite.scala
index 37e2670de9..4b838a8ab1 100644
--- a/core/src/test/scala/org/apache/spark/ui/storage/StorageTabSuite.scala
+++ b/core/src/test/scala/org/apache/spark/ui/storage/StorageTabSuite.scala
@@ -18,6 +18,7 @@
 package org.apache.spark.ui.storage
 
 import org.scalatest.BeforeAndAfter
+
 import org.apache.spark.{SparkFunSuite, Success}
 import org.apache.spark.executor.TaskMetrics
 import org.apache.spark.scheduler._
diff --git a/core/src/test/scala/org/apache/spark/util/ClosureCleanerSuite.scala b/core/src/test/scala/org/apache/spark/util/ClosureCleanerSuite.scala
index 5e745e0a95..932704c1a3 100644
--- a/core/src/test/scala/org/apache/spark/util/ClosureCleanerSuite.scala
+++ b/core/src/test/scala/org/apache/spark/util/ClosureCleanerSuite.scala
@@ -19,8 +19,8 @@ package org.apache.spark.util
 
 import java.io.NotSerializableException
 
-import org.apache.spark.LocalSparkContext._
 import org.apache.spark.{SparkContext, SparkException, SparkFunSuite, TaskContext}
+import org.apache.spark.LocalSparkContext._
 import org.apache.spark.partial.CountEvaluator
 import org.apache.spark.rdd.RDD
 
diff --git a/core/src/test/scala/org/apache/spark/util/FileAppenderSuite.scala b/core/src/test/scala/org/apache/spark/util/FileAppenderSuite.scala
index 2b76ae1f8a..98d1b28d5a 100644
--- a/core/src/test/scala/org/apache/spark/util/FileAppenderSuite.scala
+++ b/core/src/test/scala/org/apache/spark/util/FileAppenderSuite.scala
@@ -22,13 +22,12 @@ import java.io._
 import scala.collection.mutable.HashSet
 import scala.reflect._
 
-import org.scalatest.BeforeAndAfter
-
 import com.google.common.base.Charsets.UTF_8
 import com.google.common.io.Files
+import org.scalatest.BeforeAndAfter
 
 import org.apache.spark.{Logging, SparkConf, SparkFunSuite}
-import org.apache.spark.util.logging.{RollingFileAppender, SizeBasedRollingPolicy, TimeBasedRollingPolicy, FileAppender}
+import org.apache.spark.util.logging.{FileAppender, RollingFileAppender, SizeBasedRollingPolicy, TimeBasedRollingPolicy}
 
 class FileAppenderSuite extends SparkFunSuite with BeforeAndAfter with Logging {
 
diff --git a/core/src/test/scala/org/apache/spark/util/JsonProtocolSuite.scala b/core/src/test/scala/org/apache/spark/util/JsonProtocolSuite.scala
index 1939ce5c74..6566400e63 100644
--- a/core/src/test/scala/org/apache/spark/util/JsonProtocolSuite.scala
+++ b/core/src/test/scala/org/apache/spark/util/JsonProtocolSuite.scala
@@ -19,9 +19,6 @@ package org.apache.spark.util
 
 import java.util.Properties
 
-import org.apache.spark.scheduler.cluster.ExecutorInfo
-import org.apache.spark.shuffle.MetadataFetchFailedException
-
 import scala.collection.Map
 
 import org.json4s.jackson.JsonMethods._
@@ -30,6 +27,8 @@ import org.apache.spark._
 import org.apache.spark.executor._
 import org.apache.spark.rdd.RDDOperationScope
 import org.apache.spark.scheduler._
+import org.apache.spark.scheduler.cluster.ExecutorInfo
+import org.apache.spark.shuffle.MetadataFetchFailedException
 import org.apache.spark.storage._
 
 class JsonProtocolSuite extends SparkFunSuite {
diff --git a/core/src/test/scala/org/apache/spark/util/SizeEstimatorSuite.scala b/core/src/test/scala/org/apache/spark/util/SizeEstimatorSuite.scala
index fbe7b95668..49088aa0a5 100644
--- a/core/src/test/scala/org/apache/spark/util/SizeEstimatorSuite.scala
+++ b/core/src/test/scala/org/apache/spark/util/SizeEstimatorSuite.scala
@@ -19,7 +19,7 @@ package org.apache.spark.util
 
 import scala.collection.mutable.ArrayBuffer
 
-import org.scalatest.{BeforeAndAfterEach, BeforeAndAfterAll, PrivateMethodTester}
+import org.scalatest.{BeforeAndAfterAll, BeforeAndAfterEach, PrivateMethodTester}
 
 import org.apache.spark.SparkFunSuite
 
diff --git a/core/src/test/scala/org/apache/spark/util/ThreadUtilsSuite.scala b/core/src/test/scala/org/apache/spark/util/ThreadUtilsSuite.scala
index 92ae038967..6652a41b69 100644
--- a/core/src/test/scala/org/apache/spark/util/ThreadUtilsSuite.scala
+++ b/core/src/test/scala/org/apache/spark/util/ThreadUtilsSuite.scala
@@ -20,8 +20,8 @@ package org.apache.spark.util
 
 import java.util.concurrent.{CountDownLatch, TimeUnit}
 
-import scala.concurrent.duration._
 import scala.concurrent.{Await, Future}
+import scala.concurrent.duration._
 import scala.util.Random
 
 import org.scalatest.concurrent.Eventually._
diff --git a/core/src/test/scala/org/apache/spark/util/UtilsSuite.scala b/core/src/test/scala/org/apache/spark/util/UtilsSuite.scala
index 7de995af51..bc926c280c 100644
--- a/core/src/test/scala/org/apache/spark/util/UtilsSuite.scala
+++ b/core/src/test/scala/org/apache/spark/util/UtilsSuite.scala
@@ -33,8 +33,9 @@ import com.google.common.io.Files
 import org.apache.commons.lang3.SystemUtils
 import org.apache.hadoop.conf.Configuration
 import org.apache.hadoop.fs.Path
-import org.apache.spark.network.util.ByteUnit
+
 import org.apache.spark.{Logging, SparkConf, SparkFunSuite}
+import org.apache.spark.network.util.ByteUnit
 
 class UtilsSuite extends SparkFunSuite with ResetSystemProperties with Logging {
 
diff --git a/core/src/test/scala/org/apache/spark/util/collection/ExternalSorterSuite.scala b/core/src/test/scala/org/apache/spark/util/collection/ExternalSorterSuite.scala
index d7b2d07a40..a62adf1c2c 100644
--- a/core/src/test/scala/org/apache/spark/util/collection/ExternalSorterSuite.scala
+++ b/core/src/test/scala/org/apache/spark/util/collection/ExternalSorterSuite.scala
@@ -17,15 +17,13 @@
 
 package org.apache.spark.util.collection
 
-import org.apache.spark.memory.MemoryTestingUtils
-
 import scala.collection.mutable.ArrayBuffer
 import scala.util.Random
 
 import org.apache.spark._
+import org.apache.spark.memory.MemoryTestingUtils
 import org.apache.spark.serializer.{JavaSerializer, KryoSerializer}
 
-
 class ExternalSorterSuite extends SparkFunSuite with LocalSparkContext {
   import TestUtils.{assertNotSpilled, assertSpilled}
 
diff --git a/core/src/test/scala/org/apache/spark/util/collection/unsafe/sort/PrefixComparatorsSuite.scala b/core/src/test/scala/org/apache/spark/util/collection/unsafe/sort/PrefixComparatorsSuite.scala
index 0326ed70b5..c12f784471 100644
--- a/core/src/test/scala/org/apache/spark/util/collection/unsafe/sort/PrefixComparatorsSuite.scala
+++ b/core/src/test/scala/org/apache/spark/util/collection/unsafe/sort/PrefixComparatorsSuite.scala
@@ -19,6 +19,7 @@ package org.apache.spark.util.collection.unsafe.sort
 
 import com.google.common.primitives.UnsignedBytes
 import org.scalatest.prop.PropertyChecks
+
 import org.apache.spark.SparkFunSuite
 import org.apache.spark.unsafe.types.UTF8String
 
diff --git a/core/src/test/scala/org/apache/spark/util/random/RandomSamplerSuite.scala b/core/src/test/scala/org/apache/spark/util/random/RandomSamplerSuite.scala
index d6af0aebde..791491daf0 100644
--- a/core/src/test/scala/org/apache/spark/util/random/RandomSamplerSuite.scala
+++ b/core/src/test/scala/org/apache/spark/util/random/RandomSamplerSuite.scala
@@ -18,9 +18,10 @@
 package org.apache.spark.util.random
 
 import java.util.Random
+
 import scala.collection.mutable.ArrayBuffer
-import org.apache.commons.math3.distribution.PoissonDistribution
 
+import org.apache.commons.math3.distribution.PoissonDistribution
 import org.scalatest.Matchers
 
 import org.apache.spark.SparkFunSuite
diff --git a/core/src/test/scala/org/apache/spark/util/random/XORShiftRandomSuite.scala b/core/src/test/scala/org/apache/spark/util/random/XORShiftRandomSuite.scala
index a5b50fce5c..853503bbc2 100644
--- a/core/src/test/scala/org/apache/spark/util/random/XORShiftRandomSuite.scala
+++ b/core/src/test/scala/org/apache/spark/util/random/XORShiftRandomSuite.scala
@@ -17,15 +17,14 @@
 
 package org.apache.spark.util.random
 
-import org.scalatest.Matchers
+import scala.language.reflectiveCalls
 
 import org.apache.commons.math3.stat.inference.ChiSquareTest
+import org.scalatest.Matchers
 
 import org.apache.spark.SparkFunSuite
 import org.apache.spark.util.Utils.times
 
-import scala.language.reflectiveCalls
-
 class XORShiftRandomSuite extends SparkFunSuite with Matchers {
 
   private def fixture = new {