<p>java.util.NoSuchElementException: next on empty iterator</p>


<pre><code>sbt.ForkMain$ForkError: java.util.NoSuchElementException: next on empty iterator
	at scala.collection.Iterator$$anon$2.next(Iterator.scala:41)
	at scala.collection.Iterator$$anon$2.next(Iterator.scala:39)
	at scala.collection.IndexedSeqLike$Elements.next(IndexedSeqLike.scala:63)
	at scala.collection.IterableLike.head(IterableLike.scala:109)
	at scala.collection.IterableLike.head$(IterableLike.scala:108)
	at scala.collection.mutable.ArrayBuffer.scala$collection$IndexedSeqOptimized$$super$head(ArrayBuffer.scala:49)
	at scala.collection.IndexedSeqOptimized.head(IndexedSeqOptimized.scala:129)
	at scala.collection.IndexedSeqOptimized.head$(IndexedSeqOptimized.scala:129)
	at scala.collection.mutable.ArrayBuffer.head(ArrayBuffer.scala:49)
	at scala.collection.TraversableLike.last(TraversableLike.scala:519)
	at scala.collection.TraversableLike.last$(TraversableLike.scala:518)
	at scala.collection.mutable.ArrayBuffer.scala$collection$IndexedSeqOptimized$$super$last(ArrayBuffer.scala:49)
	at scala.collection.IndexedSeqOptimized.last(IndexedSeqOptimized.scala:135)
	at scala.collection.IndexedSeqOptimized.last$(IndexedSeqOptimized.scala:135)
	at scala.collection.mutable.ArrayBuffer.last(ArrayBuffer.scala:49)
	at org.apache.spark.streaming.MasterFailureTest$.testUpdateStateByKey(MasterFailureTest.scala:118)
	at org.apache.spark.streaming.FailureSuite.$anonfun$new$5(FailureSuite.scala:57)
	at scala.runtime.java8.JFunction0$mcV$sp.apply(JFunction0$mcV$sp.java:23)
	at org.scalatest.OutcomeOf.outcomeOf(OutcomeOf.scala:85)
	at org.scalatest.OutcomeOf.outcomeOf$(OutcomeOf.scala:83)
	at org.scalatest.OutcomeOf$.outcomeOf(OutcomeOf.scala:104)
	at org.scalatest.Transformer.apply(Transformer.scala:22)
	at org.scalatest.Transformer.apply(Transformer.scala:20)
	at org.scalatest.FunSuiteLike$$anon$1.apply(FunSuiteLike.scala:186)
	at org.apache.spark.SparkFunSuite.withFixture(SparkFunSuite.scala:149)
	at org.scalatest.FunSuiteLike.invokeWithFixture$1(FunSuiteLike.scala:184)
	at org.scalatest.FunSuiteLike.$anonfun$runTest$1(FunSuiteLike.scala:196)
	at org.scalatest.SuperEngine.runTestImpl(Engine.scala:289)
	at org.scalatest.FunSuiteLike.runTest(FunSuiteLike.scala:196)
	at org.scalatest.FunSuiteLike.runTest$(FunSuiteLike.scala:178)
	at org.apache.spark.SparkFunSuite.org$scalatest$BeforeAndAfterEach$$super$runTest(SparkFunSuite.scala:56)
	at org.scalatest.BeforeAndAfterEach.runTest(BeforeAndAfterEach.scala:221)
	at org.scalatest.BeforeAndAfterEach.runTest$(BeforeAndAfterEach.scala:214)
	at org.apache.spark.streaming.FailureSuite.org$scalatest$BeforeAndAfter$$super$runTest(FailureSuite.scala:32)
	at org.scalatest.BeforeAndAfter.runTest(BeforeAndAfter.scala:203)
	at org.scalatest.BeforeAndAfter.runTest$(BeforeAndAfter.scala:192)
	at org.apache.spark.streaming.FailureSuite.runTest(FailureSuite.scala:32)
	at org.scalatest.FunSuiteLike.$anonfun$runTests$1(FunSuiteLike.scala:229)
	at org.scalatest.SuperEngine.$anonfun$runTestsInBranch$1(Engine.scala:396)
	at scala.collection.immutable.List.foreach(List.scala:392)
	at org.scalatest.SuperEngine.traverseSubNodes$1(Engine.scala:384)
	at org.scalatest.SuperEngine.runTestsInBranch(Engine.scala:379)
	at org.scalatest.SuperEngine.runTestsImpl(Engine.scala:461)
	at org.scalatest.FunSuiteLike.runTests(FunSuiteLike.scala:229)
	at org.scalatest.FunSuiteLike.runTests$(FunSuiteLike.scala:228)
	at org.scalatest.FunSuite.runTests(FunSuite.scala:1560)
	at org.scalatest.Suite.run(Suite.scala:1147)
	at org.scalatest.Suite.run$(Suite.scala:1129)
	at org.scalatest.FunSuite.org$scalatest$FunSuiteLike$$super$run(FunSuite.scala:1560)
	at org.scalatest.FunSuiteLike.$anonfun$run$1(FunSuiteLike.scala:233)
	at org.scalatest.SuperEngine.runImpl(Engine.scala:521)
	at org.scalatest.FunSuiteLike.run(FunSuiteLike.scala:233)
	at org.scalatest.FunSuiteLike.run$(FunSuiteLike.scala:232)
	at org.apache.spark.SparkFunSuite.org$scalatest$BeforeAndAfterAll$$super$run(SparkFunSuite.scala:56)
	at org.scalatest.BeforeAndAfterAll.liftedTree1$1(BeforeAndAfterAll.scala:213)
	at org.scalatest.BeforeAndAfterAll.run(BeforeAndAfterAll.scala:210)
	at org.scalatest.BeforeAndAfterAll.run$(BeforeAndAfterAll.scala:208)
	at org.apache.spark.streaming.FailureSuite.org$scalatest$BeforeAndAfter$$super$run(FailureSuite.scala:32)
	at org.scalatest.BeforeAndAfter.run(BeforeAndAfter.scala:258)
	at org.scalatest.BeforeAndAfter.run$(BeforeAndAfter.scala:256)
	at org.apache.spark.streaming.FailureSuite.run(FailureSuite.scala:32)
	at org.scalatest.tools.Framework.org$scalatest$tools$Framework$$runSuite(Framework.scala:314)
	at org.scalatest.tools.Framework$ScalaTestTask.execute(Framework.scala:507)
	at sbt.ForkMain$Run$2.call(ForkMain.java:296)
	at sbt.ForkMain$Run$2.call(ForkMain.java:286)
	at java.util.concurrent.FutureTask.run(FutureTask.java:266)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
	at java.lang.Thread.run(Thread.java:748)
</code></pre>