java.lang.IllegalStateException: SparkContext has been shutdown

sbt.ForkMain$ForkError: java.lang.IllegalStateException: SparkContext has been shutdown
	at org.apache.spark.SparkContext.runJob(SparkContext.scala:2066)
	at org.apache.spark.SparkContext.runJob(SparkContext.scala:2095)
	at org.apache.spark.SparkContext.runJob(SparkContext.scala:2114)
	at org.apache.spark.SparkContext.runJob(SparkContext.scala:2139)
	at org.apache.spark.rdd.RDD$$anonfun$collect$1.apply(RDD.scala:959)
	at org.apache.spark.rdd.RDDOperationScope$.withScope(RDDOperationScope.scala:151)
	at org.apache.spark.rdd.RDDOperationScope$.withScope(RDDOperationScope.scala:112)
	at org.apache.spark.rdd.RDD.withScope(RDD.scala:364)
	at org.apache.spark.rdd.RDD.collect(RDD.scala:958)
	at org.apache.spark.sql.execution.datasources.parquet.ParquetFileFormat$.mergeSchemasInParallel(ParquetFileFormat.scala:633)
	at org.apache.spark.sql.execution.datasources.parquet.ParquetFileFormat.inferSchema(ParquetFileFormat.scala:241)
	at org.apache.spark.sql.execution.datasources.DataSource$$anonfun$6.apply(DataSource.scala:180)
	at org.apache.spark.sql.execution.datasources.DataSource$$anonfun$6.apply(DataSource.scala:180)
	at scala.Option.orElse(Option.scala:289)
	at org.apache.spark.sql.execution.datasources.DataSource.getOrInferFileFormatSchema(DataSource.scala:179)
	at org.apache.spark.sql.execution.datasources.DataSource.resolveRelation(DataSource.scala:373)
	at org.apache.spark.sql.DataFrameReader.loadV1Source(DataFrameReader.scala:224)
	at org.apache.spark.sql.DataFrameReader.load(DataFrameReader.scala:212)
	at org.apache.spark.sql.DataFrameReader.load(DataFrameReader.scala:179)
	at org.apache.spark.ml.classification.LogisticRegressionModel$LogisticRegressionModelReader.load(LogisticRegression.scala:1255)
	at org.apache.spark.ml.classification.LogisticRegressionModel$LogisticRegressionModelReader.load(LogisticRegression.scala:1245)
	at org.apache.spark.ml.util.DefaultParamsReader$.loadParamsInstance(ReadWrite.scala:652)
	at org.apache.spark.ml.tuning.CrossValidatorModel$CrossValidatorModelReader$$anonfun$2$$anonfun$apply$mcVI$sp$2.apply$mcVI$sp(CrossValidator.scala:416)
	at scala.collection.immutable.Range.foreach$mVc$sp(Range.scala:160)
	at org.apache.spark.ml.tuning.CrossValidatorModel$CrossValidatorModelReader$$anonfun$2.apply$mcVI$sp(CrossValidator.scala:413)
	at scala.collection.immutable.Range.foreach$mVc$sp(Range.scala:160)
	at org.apache.spark.ml.tuning.CrossValidatorModel$CrossValidatorModelReader.load(CrossValidator.scala:411)
	at org.apache.spark.ml.tuning.CrossValidatorModel$CrossValidatorModelReader.load(CrossValidator.scala:390)
	at org.apache.spark.ml.util.MLReadable$class.load(ReadWrite.scala:380)
	at org.apache.spark.ml.tuning.CrossValidatorModel$.load(CrossValidator.scala:340)
	at org.apache.spark.ml.tuning.CrossValidatorSuite$$anonfun$10.apply(CrossValidatorSuite.scala:227)
	at org.apache.spark.ml.tuning.CrossValidatorSuite$$anonfun$10.apply(CrossValidatorSuite.scala:201)
	at org.scalatest.OutcomeOf$class.outcomeOf(OutcomeOf.scala:85)
	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$$anon$1.apply(FunSuiteLike.scala:186)
	at org.apache.spark.SparkFunSuite.withFixture(SparkFunSuite.scala:103)
	at org.scalatest.FunSuiteLike$class.invokeWithFixture$1(FunSuiteLike.scala:183)
	at org.scalatest.FunSuiteLike$$anonfun$runTest$1.apply(FunSuiteLike.scala:196)
	at org.scalatest.FunSuiteLike$$anonfun$runTest$1.apply(FunSuiteLike.scala:196)
	at org.scalatest.SuperEngine.runTestImpl(Engine.scala:289)
	at org.scalatest.FunSuiteLike$class.runTest(FunSuiteLike.scala:196)
	at org.apache.spark.ml.tuning.CrossValidatorSuite.org$scalatest$BeforeAndAfterEach$$super$runTest(CrossValidatorSuite.scala:37)
	at org.scalatest.BeforeAndAfterEach$class.runTest(BeforeAndAfterEach.scala:221)
	at org.apache.spark.ml.tuning.CrossValidatorSuite.runTest(CrossValidatorSuite.scala:37)
	at org.scalatest.FunSuiteLike$$anonfun$runTests$1.apply(FunSuiteLike.scala:229)
	at org.scalatest.FunSuiteLike$$anonfun$runTests$1.apply(FunSuiteLike.scala:229)
	at org.scalatest.SuperEngine$$anonfun$traverseSubNodes$1$1.apply(Engine.scala:396)
	at org.scalatest.SuperEngine$$anonfun$traverseSubNodes$1$1.apply(Engine.scala:384)
	at scala.collection.immutable.List.foreach(List.scala:392)
	at org.scalatest.SuperEngine.traverseSubNodes$1(Engine.scala:384)
	at org.scalatest.SuperEngine.org$scalatest$SuperEngine$$runTestsInBranch(Engine.scala:379)
	at org.scalatest.SuperEngine.runTestsImpl(Engine.scala:461)
	at org.scalatest.FunSuiteLike$class.runTests(FunSuiteLike.scala:229)
	at org.scalatest.FunSuite.runTests(FunSuite.scala:1560)
	at org.scalatest.Suite$class.run(Suite.scala:1147)
	at org.scalatest.FunSuite.org$scalatest$FunSuiteLike$$super$run(FunSuite.scala:1560)
	at org.scalatest.FunSuiteLike$$anonfun$run$1.apply(FunSuiteLike.scala:233)
	at org.scalatest.FunSuiteLike$$anonfun$run$1.apply(FunSuiteLike.scala:233)
	at org.scalatest.SuperEngine.runImpl(Engine.scala:521)
	at org.scalatest.FunSuiteLike$class.run(FunSuiteLike.scala:233)
	at org.apache.spark.SparkFunSuite.org$scalatest$BeforeAndAfterAll$$super$run(SparkFunSuite.scala:52)
	at org.scalatest.BeforeAndAfterAll$class.liftedTree1$1(BeforeAndAfterAll.scala:213)
	at org.scalatest.BeforeAndAfterAll$class.run(BeforeAndAfterAll.scala:210)
	at org.apache.spark.SparkFunSuite.run(SparkFunSuite.scala:52)
	at org.scalatest.tools.Framework.org$scalatest$tools$Framework$$runSuite(Framework.scala:314)
	at org.scalatest.tools.Framework$ScalaTestTask.execute(Framework.scala:480)
	at sbt.ForkMain$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)