diff --git a/core/src/main/scala/org/apache/spark/deploy/history/FsHistoryProvider.scala b/core/src/main/scala/org/apache/spark/deploy/history/FsHistoryProvider.scala
index 2aea75cb27a35..ca066e4f2e20e 100644
--- a/core/src/main/scala/org/apache/spark/deploy/history/FsHistoryProvider.scala
+++ b/core/src/main/scala/org/apache/spark/deploy/history/FsHistoryProvider.scala
@@ -17,24 +17,22 @@
 
 package org.apache.spark.deploy.history
 
-import java.io.{IOException, BufferedInputStream, FileNotFoundException, InputStream}
+import java.io.{BufferedInputStream, FileNotFoundException, IOException, InputStream}
 import java.util.concurrent.{ExecutorService, Executors, TimeUnit}
 
 import scala.collection.mutable
 import scala.concurrent.duration.Duration
 
-import com.google.common.util.concurrent.ThreadFactoryBuilder
-
-import com.google.common.util.concurrent.MoreExecutors
-import org.apache.hadoop.fs.permission.AccessControlException
+import com.google.common.util.concurrent.{MoreExecutors, ThreadFactoryBuilder}
 import org.apache.hadoop.fs.{FileStatus, Path}
+import org.apache.hadoop.fs.permission.AccessControlException
+
+import org.apache.spark.{Logging, SecurityManager, SparkConf}
 import org.apache.spark.deploy.SparkHadoopUtil
 import org.apache.spark.io.CompressionCodec
 import org.apache.spark.scheduler._
 import org.apache.spark.ui.SparkUI
 import org.apache.spark.util.Utils
-import org.apache.spark.{Logging, SecurityManager, SparkConf}
-
 
 /**
  * A class that provides application history from event logs stored in the file system.
@@ -44,7 +42,7 @@ import org.apache.spark.{Logging, SecurityManager, SparkConf}
 private[history] class FsHistoryProvider(conf: SparkConf) extends ApplicationHistoryProvider
   with Logging {
 
-  import FsHistoryProvider._
+  import org.apache.spark.deploy.history.FsHistoryProvider._
 
   private val NOT_STARTED = "<Not Started>"
 
diff --git a/core/src/main/scala/org/apache/spark/deploy/history/HistoryServer.scala b/core/src/main/scala/org/apache/spark/deploy/history/HistoryServer.scala
index 67696258029de..273240d904474 100644
--- a/core/src/main/scala/org/apache/spark/deploy/history/HistoryServer.scala
+++ b/core/src/main/scala/org/apache/spark/deploy/history/HistoryServer.scala
@@ -21,11 +21,11 @@ import java.util.NoSuchElementException
 import javax.servlet.http.{HttpServlet, HttpServletRequest, HttpServletResponse}
 
 import com.google.common.cache._
-import org.apache.spark.status.api.v1.{ApplicationsListResource, ApplicationInfo, JsonRootResource, UIRoot}
 import org.eclipse.jetty.servlet.{ServletContextHandler, ServletHolder}
 
 import org.apache.spark.{Logging, SecurityManager, SparkConf}
 import org.apache.spark.deploy.SparkHadoopUtil
+import org.apache.spark.status.api.v1.{ApplicationInfo, ApplicationsListResource, JsonRootResource, UIRoot}
 import org.apache.spark.ui.{SparkUI, UIUtils, WebUI}
 import org.apache.spark.ui.JettyUtils._
 import org.apache.spark.util.SignalLogger
diff --git a/core/src/main/scala/org/apache/spark/status/api/v1/AllRDDResource.scala b/core/src/main/scala/org/apache/spark/status/api/v1/AllRDDResource.scala
index aeacd6b491caf..ed153fc308f63 100644
--- a/core/src/main/scala/org/apache/spark/status/api/v1/AllRDDResource.scala
+++ b/core/src/main/scala/org/apache/spark/status/api/v1/AllRDDResource.scala
@@ -16,10 +16,10 @@
  */
 package org.apache.spark.status.api.v1
 
-import javax.ws.rs.{PathParam, GET, Produces}
+import javax.ws.rs.{GET, PathParam, Produces}
 import javax.ws.rs.core.MediaType
 
-import org.apache.spark.storage.{StorageUtils, StorageStatus, RDDInfo}
+import org.apache.spark.storage.{RDDInfo, StorageStatus, StorageUtils}
 import org.apache.spark.ui.storage.StorageListener
 
 @Produces(Array(MediaType.APPLICATION_JSON))
diff --git a/core/src/main/scala/org/apache/spark/status/api/v1/AllStagesResource.scala b/core/src/main/scala/org/apache/spark/status/api/v1/AllStagesResource.scala
index d280934557945..f32ebb739f608 100644
--- a/core/src/main/scala/org/apache/spark/status/api/v1/AllStagesResource.scala
+++ b/core/src/main/scala/org/apache/spark/status/api/v1/AllStagesResource.scala
@@ -17,20 +17,14 @@
 package org.apache.spark.status.api.v1
 
 import java.util.Date
-import javax.ws.rs.{QueryParam, PathParam, GET, Produces}
+import javax.ws.rs.{GET, PathParam, Produces, QueryParam}
 import javax.ws.rs.core.MediaType
 
-import org.apache.spark.executor.{
-TaskMetrics => InternalTaskMetrics,
-InputMetrics => InternalInputMetrics,
-OutputMetrics => InternalOutputMetrics,
-ShuffleReadMetrics => InternalShuffleReadMetrics,
-ShuffleWriteMetrics => InternalShuffleWriteMetrics
-}
+import org.apache.spark.executor.{InputMetrics => InternalInputMetrics, OutputMetrics => InternalOutputMetrics, ShuffleReadMetrics => InternalShuffleReadMetrics, ShuffleWriteMetrics => InternalShuffleWriteMetrics, TaskMetrics => InternalTaskMetrics}
 import org.apache.spark.scheduler.StageInfo
 import org.apache.spark.status.api._
 import org.apache.spark.ui.SparkUI
-import org.apache.spark.ui.jobs.UIData.{TaskUIData, StageUIData}
+import org.apache.spark.ui.jobs.UIData.{StageUIData, TaskUIData}
 
 @Produces(Array(MediaType.APPLICATION_JSON))
 class AllStagesResource(uiRoot: UIRoot) {
diff --git a/core/src/main/scala/org/apache/spark/status/api/v1/ApplicationListResource.scala b/core/src/main/scala/org/apache/spark/status/api/v1/ApplicationListResource.scala
index ff8532381aa98..9605c1f69775b 100644
--- a/core/src/main/scala/org/apache/spark/status/api/v1/ApplicationListResource.scala
+++ b/core/src/main/scala/org/apache/spark/status/api/v1/ApplicationListResource.scala
@@ -17,8 +17,8 @@
 package org.apache.spark.status.api.v1
 
 import java.util.Date
+import javax.ws.rs.{DefaultValue, GET, Produces, QueryParam}
 import javax.ws.rs.core.MediaType
-import javax.ws.rs.{DefaultValue, QueryParam, Produces, GET}
 
 import org.apache.spark.deploy.history.ApplicationHistoryInfo
 import org.apache.spark.deploy.master.{ApplicationInfo => InternalApplicationInfo}
diff --git a/core/src/main/scala/org/apache/spark/status/api/v1/CustomObjectMapper.scala b/core/src/main/scala/org/apache/spark/status/api/v1/CustomObjectMapper.scala
index 3ded8c636aaa2..aad906699b549 100644
--- a/core/src/main/scala/org/apache/spark/status/api/v1/CustomObjectMapper.scala
+++ b/core/src/main/scala/org/apache/spark/status/api/v1/CustomObjectMapper.scala
@@ -17,13 +17,13 @@
 package org.apache.spark.status.api.v1
 
 import java.text.SimpleDateFormat
-import java.util.{SimpleTimeZone, Calendar}
+import java.util.{Calendar, SimpleTimeZone}
 import javax.ws.rs.Produces
 import javax.ws.rs.core.MediaType
 import javax.ws.rs.ext.{ContextResolver, Provider}
 
 import com.fasterxml.jackson.annotation.JsonInclude
-import com.fasterxml.jackson.databind.{SerializationFeature, ObjectMapper}
+import com.fasterxml.jackson.databind.{ObjectMapper, SerializationFeature}
 
 @Provider
 @Produces(Array(MediaType.APPLICATION_JSON))
diff --git a/core/src/main/scala/org/apache/spark/status/api/v1/ExecutorListResource.scala b/core/src/main/scala/org/apache/spark/status/api/v1/ExecutorListResource.scala
index 28f3897614c41..5cc2a0a4b727b 100644
--- a/core/src/main/scala/org/apache/spark/status/api/v1/ExecutorListResource.scala
+++ b/core/src/main/scala/org/apache/spark/status/api/v1/ExecutorListResource.scala
@@ -16,7 +16,7 @@
 */
 package org.apache.spark.status.api.v1
 
-import javax.ws.rs.{PathParam, GET, Produces}
+import javax.ws.rs.{GET, PathParam, Produces}
 import javax.ws.rs.core.MediaType
 
 import org.apache.spark.ui.exec.ExecutorsPage
diff --git a/core/src/main/scala/org/apache/spark/status/api/v1/JsonRootResource.scala b/core/src/main/scala/org/apache/spark/status/api/v1/JsonRootResource.scala
index 56b4a23af715f..6092cbdcc5f2e 100644
--- a/core/src/main/scala/org/apache/spark/status/api/v1/JsonRootResource.scala
+++ b/core/src/main/scala/org/apache/spark/status/api/v1/JsonRootResource.scala
@@ -18,19 +18,16 @@ package org.apache.spark.status.api.v1
 
 import javax.servlet.ServletContext
 import javax.ws.rs._
-import javax.ws.rs.core.{Response, Context}
+import javax.ws.rs.core.{Context, Response}
 
 import com.sun.jersey.api.core.ResourceConfig
 import com.sun.jersey.spi.container.servlet.ServletContainer
-
 import org.eclipse.jetty.server.handler.ContextHandler
-import org.eclipse.jetty.servlet.{ServletHolder, ServletContextHandler}
-import org.glassfish.jersey.jackson._
+import org.eclipse.jetty.servlet.{ServletContextHandler, ServletHolder}
 
 import org.apache.spark.SecurityManager
 import org.apache.spark.ui.SparkUI
 
-
 @Path("/v1")
 class JsonRootResource extends UIRootFromServletContext {
 
diff --git a/core/src/main/scala/org/apache/spark/status/api/v1/OneStageResource.scala b/core/src/main/scala/org/apache/spark/status/api/v1/OneStageResource.scala
index 14611de7d23ce..748dc840e7495 100644
--- a/core/src/main/scala/org/apache/spark/status/api/v1/OneStageResource.scala
+++ b/core/src/main/scala/org/apache/spark/status/api/v1/OneStageResource.scala
@@ -16,7 +16,7 @@
  */
 package org.apache.spark.status.api.v1
 
-import javax.ws.rs.{PathParam, GET, Produces}
+import javax.ws.rs.{GET, PathParam, Produces}
 import javax.ws.rs.core.MediaType
 
 import org.apache.spark.SparkException
diff --git a/core/src/main/scala/org/apache/spark/status/api/v1/SecurityFilter.scala b/core/src/main/scala/org/apache/spark/status/api/v1/SecurityFilter.scala
index 6e6dc41d8ab04..31a573431662a 100644
--- a/core/src/main/scala/org/apache/spark/status/api/v1/SecurityFilter.scala
+++ b/core/src/main/scala/org/apache/spark/status/api/v1/SecurityFilter.scala
@@ -19,7 +19,7 @@ package org.apache.spark.status.api.v1
 import javax.ws.rs.WebApplicationException
 import javax.ws.rs.core.Response
 
-import com.sun.jersey.spi.container.{ContainerRequest,ContainerRequestFilter}
+import com.sun.jersey.spi.container.{ContainerRequest, ContainerRequestFilter}
 
 class SecurityFilter extends ContainerRequestFilter with UIRootFromServletContext {
   def filter(req: ContainerRequest): ContainerRequest = {
diff --git a/core/src/main/scala/org/apache/spark/status/api/v1/StageData.scala b/core/src/main/scala/org/apache/spark/status/api/v1/StageData.scala
index d66ebfec86b95..df1a6f0d599bd 100644
--- a/core/src/main/scala/org/apache/spark/status/api/v1/StageData.scala
+++ b/core/src/main/scala/org/apache/spark/status/api/v1/StageData.scala
@@ -17,10 +17,10 @@
 
 package org.apache.spark.status.api.v1
 
-import org.apache.spark.status.api.StageStatus
-
 import scala.collection.Map
 
+import org.apache.spark.status.api.StageStatus
+
 case class StageData(
   status: StageStatus,
   stageId: Int,
diff --git a/core/src/test/scala/org/apache/spark/deploy/history/HistoryServerSuite.scala b/core/src/test/scala/org/apache/spark/deploy/history/HistoryServerSuite.scala
index 645edd7e0a47e..4b81942421fc8 100644
--- a/core/src/test/scala/org/apache/spark/deploy/history/HistoryServerSuite.scala
+++ b/core/src/test/scala/org/apache/spark/deploy/history/HistoryServerSuite.scala
@@ -16,19 +16,16 @@
  */
 package org.apache.spark.deploy.history
 
-import java.io.{IOException, FileInputStream, FileWriter, File}
+import java.io.{File, FileInputStream, FileWriter, IOException}
 import java.net.{HttpURLConnection, URL}
 import javax.servlet.http.{HttpServletRequest, HttpServletResponse}
 
 import org.apache.commons.io.{FileUtils, IOUtils}
-
-import org.apache.spark.{SecurityManager, SparkConf}
-import org.scalatest.{BeforeAndAfter, Matchers, FunSuite}
-
-import org.apache.hadoop.fs.Path
-import org.mockito.Mockito.{when}
+import org.mockito.Mockito.when
+import org.scalatest.{BeforeAndAfter, FunSuite, Matchers}
 import org.scalatest.mock.MockitoSugar
 
+import org.apache.spark.{SecurityManager, SparkConf}
 import org.apache.spark.ui.SparkUI
 
 class HistoryServerSuite extends FunSuite with BeforeAndAfter with Matchers with MockitoSugar {