Return-Path: X-Original-To: apmail-flink-issues-archive@minotaur.apache.org Delivered-To: apmail-flink-issues-archive@minotaur.apache.org Received: from mail.apache.org (hermes.apache.org [140.211.11.3]) by minotaur.apache.org (Postfix) with SMTP id 463B818042 for ; Fri, 16 Oct 2015 17:06:08 +0000 (UTC) Received: (qmail 72417 invoked by uid 500); 16 Oct 2015 17:06:05 -0000 Delivered-To: apmail-flink-issues-archive@flink.apache.org Received: (qmail 72370 invoked by uid 500); 16 Oct 2015 17:06:05 -0000 Mailing-List: contact issues-help@flink.apache.org; run by ezmlm Precedence: bulk List-Help: List-Unsubscribe: List-Post: List-Id: Reply-To: dev@flink.apache.org Delivered-To: mailing list issues@flink.apache.org Received: (qmail 72360 invoked by uid 99); 16 Oct 2015 17:06:05 -0000 Received: from arcas.apache.org (HELO arcas.apache.org) (140.211.11.28) by apache.org (qpsmtpd/0.29) with ESMTP; Fri, 16 Oct 2015 17:06:05 +0000 Date: Fri, 16 Oct 2015 17:06:05 +0000 (UTC) From: "ASF GitHub Bot (JIRA)" To: issues@flink.apache.org Message-ID: In-Reply-To: References: Subject: [jira] [Commented] (FLINK-2809) DataSet[Unit] doesn't work MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-JIRA-FingerPrint: 30527f35849b9dde25b450d4833f0394 [ https://issues.apache.org/jira/browse/FLINK-2809?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14961010#comment-14961010 ] ASF GitHub Bot commented on FLINK-2809: --------------------------------------- Github user StephanEwen commented on the pull request: https://github.com/apache/flink/pull/1217#issuecomment-148773959 Apparently you can sometimes get weird behavior if you confuse the two cases, because extra parenthesis are then accidentally interpreted as a call to "apply()". > DataSet[Unit] doesn't work > -------------------------- > > Key: FLINK-2809 > URL: https://issues.apache.org/jira/browse/FLINK-2809 > Project: Flink > Issue Type: Bug > Components: Scala API > Reporter: Gabor Gevay > Assignee: Gabor Gevay > Priority: Minor > > The following code creates a DataSet\[Unit\]: > val env = ExecutionEnvironment.createLocalEnvironment() > val a = env.fromElements(1,2,3) > val b = a.map (_ => ()) > b.writeAsText("/tmp/xxx") > env.execute() > This doesn't work, because a VoidSerializer is created, which can't cope with a BoxedUnit. See exception below. > I'm now thinking about creating a UnitSerializer class. > org.apache.flink.runtime.client.JobExecutionException: Job execution failed. > at org.apache.flink.runtime.jobmanager.JobManager$$anonfun$receiveWithLogMessages$1.applyOrElse(JobManager.scala:314) > at scala.runtime.AbstractPartialFunction.apply(AbstractPartialFunction.scala:36) > at org.apache.flink.runtime.ActorLogMessages$$anon$1.apply(ActorLogMessages.scala:36) > at org.apache.flink.runtime.ActorLogMessages$$anon$1.apply(ActorLogMessages.scala:29) > at scala.PartialFunction$class.applyOrElse(PartialFunction.scala:123) > at org.apache.flink.runtime.ActorLogMessages$$anon$1.applyOrElse(ActorLogMessages.scala:29) > at akka.actor.Actor$class.aroundReceive(Actor.scala:465) > at org.apache.flink.runtime.jobmanager.JobManager.aroundReceive(JobManager.scala:92) > at akka.actor.ActorCell.receiveMessage(ActorCell.scala:516) > at akka.actor.ActorCell.invoke(ActorCell.scala:487) > at akka.dispatch.Mailbox.processMailbox(Mailbox.scala:254) > at akka.dispatch.Mailbox.run(Mailbox.scala:221) > at akka.dispatch.Mailbox.exec(Mailbox.scala:231) > at scala.concurrent.forkjoin.ForkJoinTask.doExec(ForkJoinTask.java:260) > at scala.concurrent.forkjoin.ForkJoinPool$WorkQueue.runTask(ForkJoinPool.java:1339) > at scala.concurrent.forkjoin.ForkJoinPool.runWorker(ForkJoinPool.java:1979) > at scala.concurrent.forkjoin.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:107) > Caused by: java.lang.ClassCastException: scala.runtime.BoxedUnit cannot be cast to java.lang.Void > at org.apache.flink.api.common.typeutils.base.VoidSerializer.serialize(VoidSerializer.java:26) > at org.apache.flink.runtime.plugable.SerializationDelegate.write(SerializationDelegate.java:51) > at org.apache.flink.runtime.io.network.api.serialization.SpanningRecordSerializer.addRecord(SpanningRecordSerializer.java:76) > at org.apache.flink.runtime.io.network.api.writer.RecordWriter.emit(RecordWriter.java:83) > at org.apache.flink.runtime.operators.shipping.OutputCollector.collect(OutputCollector.java:65) > at org.apache.flink.runtime.operators.chaining.ChainedMapDriver.collect(ChainedMapDriver.java:78) > at org.apache.flink.runtime.operators.DataSourceTask.invoke(DataSourceTask.java:177) > at org.apache.flink.runtime.taskmanager.Task.run(Task.java:564) > at java.lang.Thread.run(Thread.java:745) -- This message was sent by Atlassian JIRA (v6.3.4#6332)