Minor styling

Author: ifilonenko

resource-managers/kubernetes/core/src/main/scala/org/apache/spark/deploy/kubernetes/HadoopConfBootstrap.scala

@@ -18,21 +18,19 @@ package org.apache.spark.deploy.kubernetes
 
 import java.io.File
 
-import org.apache.spark.deploy.kubernetes.constants._
-import io.fabric8.kubernetes.api.model.{ConfigMapBuilder, ContainerBuilder, KeyToPathBuilder, PodBuilder}
-
-import collection.JavaConverters._
+import io.fabric8.kubernetes.api.model.{ContainerBuilder, KeyToPathBuilder, PodBuilder}
 
+import org.apache.spark.deploy.kubernetes.constants._
 
 /**
-  * This is separated out from the HadoopConf steps API because this component can be reused to
-  * set up the hadoop-conf for executors as well.
-  */
+ * This is separated out from the HadoopConf steps API because this component can be reused to
+ * set up the hadoop-conf for executors as well.
+ */
 private[spark] trait HadoopConfBootstrap {
-  /**
-    * Bootstraps a main container with the ConfigMaps mounted as volumes and an ENV variable
-    * pointing to the mounted file.
-    */
+ /**
+  * Bootstraps a main container with the ConfigMaps mounted as volumes and an ENV variable
+  * pointing to the mounted file.
+  */
   def bootstrapMainContainerAndVolumes(
     originalPodWithMainContainer: PodWithMainContainer)
   : PodWithMainContainer
@@ -45,6 +43,7 @@ private[spark] class HadoopConfBootstrapImpl(
   override def bootstrapMainContainerAndVolumes(
     originalPodWithMainContainer: PodWithMainContainer)
     : PodWithMainContainer = {
+    import collection.JavaConverters._
     val fileContents = hadoopConfigFiles.map(file => (file.getPath, file.toString)).toMap
     val keyPaths = hadoopConfigFiles.map(file =>
       new KeyToPathBuilder().withKey(file.getPath).withPath(file.getAbsolutePath).build())
@@ -75,4 +74,4 @@ private[spark] class HadoopConfBootstrapImpl(
       mainContainerWithMountedHadoopConf
     )
   }
-}
+}

resource-managers/kubernetes/core/src/main/scala/org/apache/spark/deploy/kubernetes/submit/DriverConfigurationStepsOrchestrator.scala

@@ -22,8 +22,8 @@ import org.apache.spark.SparkConf
 import org.apache.spark.deploy.kubernetes.ConfigurationUtils
 import org.apache.spark.deploy.kubernetes.config._
 import org.apache.spark.deploy.kubernetes.constants._
-import org.apache.spark.deploy.kubernetes.submit.submitsteps.hadoopsteps.HadoopStepsOrchestrator
 import org.apache.spark.deploy.kubernetes.submit.submitsteps._
+import org.apache.spark.deploy.kubernetes.submit.submitsteps.hadoopsteps.HadoopStepsOrchestrator
 import org.apache.spark.deploy.kubernetes.submit.submitsteps.initcontainer.InitContainerConfigurationStepsOrchestrator
 import org.apache.spark.launcher.SparkLauncher
 import org.apache.spark.util.Utils

resource-managers/kubernetes/core/src/main/scala/org/apache/spark/deploy/kubernetes/submit/submitsteps/hadoopsteps/HadoopConfMounterStep.scala

@@ -16,15 +16,7 @@
  */
 package org.apache.spark.deploy.kubernetes.submit.submitsteps.hadoopsteps
 
-import java.io.File
-
-import io.fabric8.kubernetes.api.model._
 import org.apache.spark.deploy.kubernetes.{HadoopConfBootstrap, PodWithMainContainer}
-import org.apache.spark.deploy.kubernetes.config._
-import org.apache.spark.deploy.kubernetes.constants._
-import org.apache.spark.deploy.kubernetes.submit.KubernetesFileUtils
-import org.apache.spark.deploy.kubernetes.submit.submitsteps.{DriverKubernetesCredentialsStep, KubernetesDriverSpec}
-import scala.collection.JavaConverters._
 
  /**
   * Step that configures the ConfigMap + Volumes for the driver
@@ -46,4 +38,4 @@ private[spark] class HadoopConfMounterStep(
        driverContainer = bootstrappedPodAndMainContainer.mainContainer
      )
   }
-}
+}

resource-managers/kubernetes/core/src/main/scala/org/apache/spark/scheduler/cluster/kubernetes/KubernetesClusterManager.scala

@@ -19,15 +19,15 @@ package org.apache.spark.scheduler.cluster.kubernetes
 import java.io.File
 
 import io.fabric8.kubernetes.client.Config
-import org.apache.spark.SparkContext
-import org.apache.spark.deploy.kubernetes.{HadoopConfBootstrapImpl, InitContainerResourceStagingServerSecretPluginImpl, SparkKubernetesClientFactory, SparkPodInitContainerBootstrapImpl}
+
+import org.apache.spark.deploy.kubernetes.{InitContainerResourceStagingServerSecretPluginImpl, SparkKubernetesClientFactory, SparkPodInitContainerBootstrapImpl}
 import org.apache.spark.deploy.kubernetes.config._
 import org.apache.spark.deploy.kubernetes.constants._
 import org.apache.spark.internal.Logging
 import org.apache.spark.scheduler.{ExternalClusterManager, SchedulerBackend, TaskScheduler, TaskSchedulerImpl}
 
 private[spark] class KubernetesClusterManager extends ExternalClusterManager with Logging {
-
+  import org.apache.spark.SparkContext
   override def canCreate(masterURL: String): Boolean = masterURL.startsWith("k8s")
 
   override def createTaskScheduler(sc: SparkContext, masterURL: String): TaskScheduler = {