Fix a few minor style / formatting nits.

Reset listener after each test
Don't null listener out at end of main().

Author: JoshRosen

core/src/main/scala/org/apache/spark/scheduler/cluster/CoarseGrainedClusterMessage.scala

@@ -39,8 +39,12 @@ private[spark] object CoarseGrainedClusterMessages {
   case class RegisterExecutorFailed(message: String) extends CoarseGrainedClusterMessage
 
   // Executors to driver
-  case class RegisterExecutor(executorId: String, hostPort: String, cores: Int,
-    logUrls : Map[String, String]) extends CoarseGrainedClusterMessage {
+  case class RegisterExecutor(
+      executorId: String,
+      hostPort: String,
+      cores: Int,
+      logUrls: Map[String, String])
+    extends CoarseGrainedClusterMessage {
     Utils.checkHostPort(hostPort, "Expected host port")
   }
 

core/src/main/scala/org/apache/spark/scheduler/cluster/ExecutorData.scala

@@ -34,5 +34,5 @@ private[cluster] class ExecutorData(
    override val executorHost: String,
    var freeCores: Int,
    override val totalCores: Int,
-   override val logUrlMap : Map[String, String]
+   override val logUrlMap: Map[String, String]
 ) extends ExecutorInfo(executorHost, totalCores, logUrlMap)

core/src/main/scala/org/apache/spark/ui/exec/ExecutorsPage.scala

@@ -26,6 +26,7 @@ import org.apache.spark.ui.{ToolTips, UIUtils, WebUIPage}
 import org.apache.spark.util.Utils
 
 /** Summary information about an executor to display in the UI. */
+// Needs to be private[ui] because of a false positive MiMa failure.
 private[ui] case class ExecutorSummaryInfo(
     id: String,
     hostPort: String,
@@ -41,7 +42,7 @@ private[ui] case class ExecutorSummaryInfo(
     totalShuffleRead: Long,
     totalShuffleWrite: Long,
     maxMemory: Long,
-    executorLogs : Map[String, String])
+    executorLogs: Map[String, String])
 
 private[ui] class ExecutorsPage(
     parent: ExecutorsTab,
@@ -144,13 +145,15 @@ private[ui] class ExecutorsPage(
       {
         if (logsExist) {
           <td>
-            {info.executorLogs.map { entry => {
-            <div>
-              <a href={s"${entry._2}"}>
-                {entry._1}
-              </a>
-            </div>}
-            }}
+            {
+              info.executorLogs.map { case (logName, logUrl) =>
+                <div>
+                  <a href={logUrl}>
+                    {logName}
+                  </a>
+                </div>
+              }
+            }
           </td>
         }
       }

core/src/main/scala/org/apache/spark/ui/exec/ExecutorsTab.scala

@@ -17,8 +17,6 @@
 
 package org.apache.spark.ui.exec
 
-import org.apache.spark.{SparkEnv, Logging, SparkException, TaskState}
-
 import scala.collection.mutable.HashMap
 
 import org.apache.spark.ExceptionFailure
@@ -57,7 +55,7 @@ class ExecutorsListener(storageStatusListener: StorageStatusListener) extends Sp
 
   def storageStatusList = storageStatusListener.storageStatusList
 
-  override def onExecutorAdded(executorAdded : SparkListenerExecutorAdded) = synchronized {
+  override def onExecutorAdded(executorAdded: SparkListenerExecutorAdded) = synchronized {
     val eid = executorAdded.executorId
     executorToLogUrls(eid) = executorAdded.executorInfo.logUrlMap
   }

core/src/test/scala/org/apache/spark/deploy/LogUrlsStandaloneSuite.scala

@@ -17,15 +17,15 @@
 
 package org.apache.spark.deploy
 
+import scala.collection.mutable
+
+import org.scalatest.{BeforeAndAfter, FunSuite}
+
 import org.apache.spark.scheduler.cluster.ExecutorInfo
 import org.apache.spark.scheduler.{SparkListenerExecutorAdded, SparkListener}
 import org.apache.spark.{SparkContext, LocalSparkContext}
-import org.scalatest.{BeforeAndAfter, BeforeAndAfterAll, FunSuite}
 
-import scala.collection.mutable
-
-class LogUrlsStandaloneSuite extends FunSuite with LocalSparkContext
-  with BeforeAndAfter with BeforeAndAfterAll {
+class LogUrlsStandaloneSuite extends FunSuite with LocalSparkContext with BeforeAndAfter {
 
   /** Length of time to wait while draining listener events. */
   val WAIT_TIMEOUT_MILLIS = 10000
@@ -44,15 +44,15 @@ class LogUrlsStandaloneSuite extends FunSuite with LocalSparkContext
     rdd2.count()
 
     assert(sc.listenerBus.waitUntilEmpty(WAIT_TIMEOUT_MILLIS))
-    listener.addedExecutorInfos.foreach(e => {
-      assert(e._2.logUrlMap.nonEmpty)
-    })
+    listener.addedExecutorInfos.values.foreach { info =>
+      assert(info.logUrlMap.nonEmpty)
+    }
   }
 
   private class SaveExecutorInfo extends SparkListener {
     val addedExecutorInfos = mutable.Map[String, ExecutorInfo]()
 
-    override def onExecutorAdded(executor : SparkListenerExecutorAdded) {
+    override def onExecutorAdded(executor: SparkListenerExecutorAdded) {
       addedExecutorInfos(executor.executorId) = executor.executorInfo
     }
   }

yarn/src/test/scala/org/apache/spark/deploy/yarn/YarnClusterSuite.scala

@@ -29,10 +29,10 @@ import org.apache.hadoop.yarn.conf.YarnConfiguration
 import org.apache.hadoop.yarn.server.MiniYARNCluster
 import org.scalatest.{BeforeAndAfterAll, FunSuite, Matchers}
 
+import org.apache.spark.{Logging, SparkConf, SparkContext, SparkException}
 import org.apache.spark.scheduler.cluster.ExecutorInfo
 import org.apache.spark.scheduler.{SparkListener, SparkListenerExecutorAdded}
 import org.apache.spark.util.Utils
-import org.apache.spark.{Logging, SparkConf, SparkContext, SparkException}
 
 class YarnClusterSuite extends FunSuite with BeforeAndAfterAll with Matchers with Logging {
 
@@ -146,9 +146,9 @@ class YarnClusterSuite extends FunSuite with BeforeAndAfterAll with Matchers wit
     checkResult(result)
 
     // verify log urls are present
-    YarnClusterDriver.listener.addedExecutorInfos.foreach(e => {
-      assert(e._2.logUrlMap.nonEmpty)
-    })
+    YarnClusterDriver.listener.addedExecutorInfos.values.foreach { info =>
+      assert(info.logUrlMap.nonEmpty)
+    }
   }
 
   test("run Spark in yarn-cluster mode") {
@@ -164,9 +164,9 @@ class YarnClusterSuite extends FunSuite with BeforeAndAfterAll with Matchers wit
     checkResult(result)
 
     // verify log urls are present.
-    YarnClusterDriver.listener.addedExecutorInfos.foreach { e => {
-      assert(e._2.logUrlMap.nonEmpty)
-    }}
+    YarnClusterDriver.listener.addedExecutorInfos.values.foreach { info =>
+      assert(info.logUrlMap.nonEmpty)
+    }
   }
 
   test("run Spark in yarn-cluster mode unsuccessfully") {
@@ -225,7 +225,7 @@ private class SaveExecutorInfo extends SparkListener {
 private object YarnClusterDriver extends Logging with Matchers {
 
   val WAIT_TIMEOUT_MILLIS = 10000
-  val listener = new SaveExecutorInfo
+  var listener: SaveExecutorInfo = null
 
   def main(args: Array[String]) = {
     if (args.length != 2) {
@@ -238,7 +238,7 @@ private object YarnClusterDriver extends Logging with Matchers {
       System.exit(1)
     }
 
-
+    listener = new SaveExecutorInfo
     val sc = new SparkContext(new SparkConf().setMaster(args(0))
       .setAppName("yarn \"test app\" 'with quotes' and \\back\\slashes and $dollarSigns"))
     sc.addSparkListener(listener)