Fix SPARK-1609: Executor fails to start when Command.extraJavaOptions...

Fix SPARK-1609:  Executor fails to start when Command.extraJavaOptions contains multiple Java options

Author: witgo <witgo@qq.com>

Closes #547 from witgo/SPARK-1609 and squashes the following commits:

deb6a4c [witgo] review commit
91da0bb [witgo] Merge branch 'master' of https://github.com/apache/spark into SPARK-1609
0640852 [witgo] review commit
8f90b22 [witgo] Merge branch 'master' of https://github.com/apache/spark into SPARK-1609
bcf36cb [witgo] Merge branch 'master' of https://github.com/apache/spark into SPARK-1609
1185605 [witgo] fix extraJavaOptions split
f7c0ab7 [witgo] bugfix
86fc4bb [witgo] bugfix
8a265b7 [witgo] Fix SPARK-1609: Executor fails to start when use spark-submit

core/src/main/scala/org/apache/spark/deploy/worker/CommandUtils.scala

@@ -48,7 +48,8 @@ object CommandUtils extends Logging {
   def buildJavaOpts(command: Command, memory: Int, sparkHome: String): Seq[String] = {
     val memoryOpts = Seq(s"-Xms${memory}M", s"-Xmx${memory}M")
     // Note, this will coalesce multiple options into a single command component
-    val extraOpts = command.extraJavaOptions.toSeq
+    val extraOpts = command.extraJavaOptions.map(Utils.splitCommandString).getOrElse(Seq())
+
     val libraryOpts =
       if (command.libraryPathEntries.size > 0) {
         val joined = command.libraryPathEntries.mkString(File.pathSeparator)
@@ -62,10 +63,10 @@ object CommandUtils extends Logging {
     val classPath = Utils.executeAndGetOutput(
       Seq(sparkHome + "/bin/compute-classpath" + ext),
       extraEnvironment=command.environment)
-    val userClassPath = command.classPathEntries.mkString(File.pathSeparator)
-    val classPathWithUser = classPath + File.pathSeparator + userClassPath
+    val userClassPath = command.classPathEntries ++ Seq(classPath)
 
-    Seq("-cp", classPathWithUser) ++ libraryOpts ++ extraOpts ++ memoryOpts
+    Seq("-cp", userClassPath.filterNot(_.isEmpty).mkString(File.pathSeparator)) ++
+      libraryOpts ++ extraOpts ++ memoryOpts
   }
 
   /** Spawn a thread that will redirect a given stream to a file */