I am starting to work with Spark datasets, I am facing this exception when I execute a groupby in Spark 1.6.1
case class RecordIdDate(recordId: String, date: String)
val ds = sc.parallelize(List(RecordIdDate("hello","1"), RecordIdDate("bye","2"))).toDS
ds.groupBy(_.recordId).mapGroups{case (id, it) => it.toSeq }
This is the exception
scala.reflect.internal.MissingRequirementError: object $line19.$read not found. at scala.reflect.internal.MissingRequirementError$.signal(MissingRequirementError.scala:16) at scala.reflect.internal.MissingRequirementError$.notFound(MissingRequirementError.scala:17) at scala.reflect.internal.Mirrors$RootsBase.ensureModuleSymbol(Mirrors.scala:126) at scala.reflect.internal.Mirrors$RootsBase.staticModule(Mirrors.scala:161) at scala.reflect.internal.Mirrors$RootsBase.staticModule(Mirrors.scala:21) at $iwC$$iwC$$iwC$$iwC$$iwC$$iwC$$iwC$$iwC$$typecreator2$1.apply(:32) at scala.reflect.api.TypeTags$WeakTypeTagImpl.tpe$lzycompute(TypeTags.scala:231) at scala.reflect.api.TypeTags$WeakTypeTagImpl.tpe(TypeTags.scala:231) at org.apache.spark.sql.SQLImplicits$$typecreator10$1.apply(SQLImplicits.scala:96) at scala.reflect.api.TypeTags$WeakTypeTagImpl.tpe$lzycompute(TypeTags.scala:231) at scala.reflect.api.TypeTags$WeakTypeTagImpl.tpe(TypeTags.scala:231) at org.apache.spark.sql.catalyst.encoders.ExpressionEncoder$.apply(ExpressionEncoder.scala:50) at org.apache.spark.sql.SQLImplicits.newProductSeqEncoder(SQLImplicits.scala:96) at $iwC$$iwC$$iwC$$iwC$$iwC$$iwC$$iwC$$iwC.(:32) at $iwC$$iwC$$iwC$$iwC$$iwC$$iwC$$iwC.(:37) at $iwC$$iwC$$iwC$$iwC$$iwC$$iwC.(:39) at $iwC$$iwC$$iwC$$iwC$$iwC.(:41) at $iwC$$iwC$$iwC$$iwC.(:43) at $iwC$$iwC$$iwC.(:45) at $iwC$$iwC.(:47) at $iwC.(:49) at (:51) at .(:55) at .() at .(:7) at .() at $print() at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:606) at org.apache.spark.repl.SparkIMain$ReadEvalPrint.call(SparkIMain.scala:1065) at org.apache.spark.repl.SparkIMain$Request.loadAndRun(SparkIMain.scala:1346) at org.apache.spark.repl.SparkIMain.loadAndRunReq$1(SparkIMain.scala:840) at org.apache.spark.repl.SparkIMain.interpret(SparkIMain.scala:871) at org.apache.spark.repl.SparkIMain.interpret(SparkIMain.scala:819) at org.apache.spark.repl.SparkILoop.reallyInterpret$1(SparkILoop.scala:857) at org.apache.spark.repl.SparkILoop.interpretStartingWith(SparkILoop.scala:902) at org.apache.spark.repl.SparkILoop.command(SparkILoop.scala:814) at org.apache.spark.repl.SparkILoop.processLine$1(SparkILoop.scala:657) at org.apache.spark.repl.SparkILoop.innerLoop$1(SparkILoop.scala:665) at org.apache.spark.repl.SparkILoop.org$apache$spark$repl$SparkILoop$$loop(SparkILoop.scala:670) at org.apache.spark.repl.SparkILoop$$anonfun$org$apache$spark$repl$SparkILoop$$process$1.apply$mcZ$sp(SparkILoop.scala:997) at org.apache.spark.repl.SparkILoop$$anonfun$org$apache$spark$repl$SparkILoop$$process$1.apply(SparkILoop.scala:945) at org.apache.spark.repl.SparkILoop$$anonfun$org$apache$spark$repl$SparkILoop$$process$1.apply(SparkILoop.scala:945) at scala.tools.nsc.util.ScalaClassLoader$.savingContextLoader(ScalaClassLoader.scala:135) at org.apache.spark.repl.SparkILoop.org$apache$spark$repl$SparkILoop$$process(SparkILoop.scala:945) at org.apache.spark.repl.SparkILoop.process(SparkILoop.scala:1059) at org.apache.spark.repl.Main$.main(Main.scala:31) at org.apache.spark.repl.Main.main(Main.scala) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:606) at org.apache.spark.deploy.SparkSubmit$.org$apache$spark$deploy$SparkSubmit$$runMain(SparkSubmit.scala:731) at org.apache.spark.deploy.SparkSubmit$.doRunMain$1(SparkSubmit.scala:181) at org.apache.spark.deploy.SparkSubmit$.submit(SparkSubmit.scala:206) at org.apache.spark.deploy.SparkSubmit$.main(SparkSubmit.scala:121) at org.apache.spark.deploy.SparkSubmit.main(SparkSubmit.scala)
Anyone can help?