Hi Team, I am new to Spark and learning. I am trying to read image files into spark job. This is how I am doing: Step 1. Created sequence files with FileName as Key and Binary image as value. i.e. Text and BytesWritable. I am able to read these sequence files into Map Reduce programs.
Step 2. I understand that Text and BytesWritable are Non Serializable therefore, I read the sequence file in Spark as following: SparkConf sparkConf = new SparkConf().setAppName("JavaSequenceFile"); JavaSparkContext ctx = new JavaSparkContext(sparkConf); JavaPairRDD<String, Byte> seqFiles = ctx.sequenceFile(args[0], String.class, Byte.class) ; final List<Tuple2<String, Byte>> tuple2s = seqFiles.collect(); The moment I try to call collect() method to get the keys of sequence file, following exception has been thrown Can any one help me understanding why collect() method is failing? If I use toArray() on seqFiles object then also I am getting same call stack. Regards Tapan java.io.NotSerializableException: org.apache.hadoop.io.Text at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1183) at java.io.ObjectOutputStream.defaultWriteFields(ObjectOutputStream.java:1547) at java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1508) at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1431) at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1177) at java.io.ObjectOutputStream.writeArray(ObjectOutputStream.java:1377) at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1173) at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:347) at org.apache.spark.serializer.JavaSerializationStream.writeObject(JavaSerializer.scala:42) at org.apache.spark.serializer.JavaSerializerInstance.serialize(JavaSerializer.scala:73) at org.apache.spark.executor.Executor$TaskRunner.run(Executor.scala:206) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615) at java.lang.Thread.run(Thread.java:745) 2015-05-19 15:15:03,705 ERROR [task-result-getter-0] scheduler.TaskSetManager (Logging.scala:logError(75)) - Task 0.0 in stage 0.0 (TID 0) had a not serializable result: org.apache.hadoop.io.Text; not retrying 2015-05-19 15:15:03,731 INFO [task-result-getter-0] scheduler.TaskSchedulerImpl (Logging.scala:logInfo(59)) - Removed TaskSet 0.0, whose tasks have all completed, from pool 2015-05-19 15:15:03,739 INFO [sparkDriver-akka.actor.default-dispatcher-2] scheduler.TaskSchedulerImpl (Logging.scala:logInfo(59)) - Cancelling stage 0 2015-05-19 15:15:03,747 INFO [main] scheduler.DAGScheduler (Logging.scala:logInfo(59)) - Job 0 failed: collect at JavaSequenceFile.java:44, took 4.421397 s Exception in thread "main" org.apache.spark.SparkException: Job aborted due to stage failure: Task 0.0 in stage 0.0 (TID 0) had a not serializable result: org.apache.hadoop.io.Text at org.apache.spark.scheduler.DAGScheduler.org$apache$spark$scheduler$DAGScheduler$$failJobAndIndependentStages(DAGScheduler.scala:1214) at org.apache.spark.scheduler.DAGScheduler$$anonfun$abortStage$1.apply(DAGScheduler.scala:1203) at org.apache.spark.scheduler.DAGScheduler$$anonfun$abortStage$1.apply(DAGScheduler.scala:1202) at scala.collection.mutable.ResizableArray$class.foreach(ResizableArray.scala:59) at scala.collection.mutable.ArrayBuffer.foreach(ArrayBuffer.scala:47) at org.apache.spark.scheduler.DAGScheduler.abortStage(DAGScheduler.scala:1202) at org.apache.spark.scheduler.DAGScheduler$$anonfun$handleTaskSetFailed$1.apply(DAGScheduler.scala:696) at org.apache.spark.scheduler.DAGScheduler$$anonfun$handleTaskSetFailed$1.apply(DAGScheduler.scala:696) at scala.Option.foreach(Option.scala:236) at org.apache.spark.scheduler.DAGScheduler.handleTaskSetFailed(DAGScheduler.scala:696) at org.apache.spark.scheduler.DAGSchedulerEventProcessActor$$anonfun$receive$2.applyOrElse(DAGScheduler.scala:1420) at akka.actor.ActorCell.receiveMessage(ActorCell.scala:498) at akka.actor.ActorCell.invoke(ActorCell.scala:456) at akka.dispatch.Mailbox.processMailbox(Mailbox.scala:237) at akka.dispatch.Mailbox.run(Mailbox.scala:219) at akka.dispatch.ForkJoinExecutorConfigurator$AkkaForkJoinTask.exec(AbstractDispatcher.scala:386) 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) -- View this message in context: http://apache-spark-user-list.1001560.n3.nabble.com/Reading-Binary-files-in-Spark-program-tp22942.html Sent from the Apache Spark User List mailing list archive at Nabble.com. --------------------------------------------------------------------- To unsubscribe, e-mail: user-unsubscr...@spark.apache.org For additional commands, e-mail: user-h...@spark.apache.org