Test Spark Scala with Maven Got Error: java.lang.NoClassDefFoundError - scala

I tried to Test Spark Scala on Scala IDE (eclipse) with Maven but keep getting error:
Exception in thread "main" java.lang.NoClassDefFoundError: org/apache/hadoop/fs/FSDataInputStream
at org.apache.spark.SparkConf.loadFromSystemProperties(SparkConf.scala:73)
at org.apache.spark.SparkConf.<init>(SparkConf.scala:68)
at org.apache.spark.SparkConf.<init>(SparkConf.scala:55)
at org.apache.spark.sql.SparkSession$Builder$$anonfun$6.apply(SparkSession.scala:904)
at org.apache.spark.sql.SparkSession$Builder$$anonfun$6.apply(SparkSession.scala:901)
at scala.Option.getOrElse(Option.scala:121)
at org.apache.spark.sql.SparkSession$Builder.getOrCreate(SparkSession.scala:901)
at com.SimpleApp$.main(SimpleApp.scala:7)
at com.SimpleApp.main(SimpleApp.scala)
Caused by: java.lang.ClassNotFoundException: org.apache.hadoop.fs.FSDataInputStream
at java.net.URLClassLoader.findClass(URLClassLoader.java:381)
at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:349)
at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
... 9 more
The program I try is the Quick Start code, from the Spark Documentation:
import org.apache.spark.sql.SparkSession
object SimpleApp {
def main(args: Array[String]) {
val logFile = "YOUR_SPARK_HOME/README.md" // Should be some file on your system
val spark = SparkSession.builder.appName("Simple Application").getOrCreate()
val logData = spark.read.textFile(logFile).cache()
val numAs = logData.filter(line => line.contains("a")).count()
val numBs = logData.filter(line => line.contains("b")).count()
println(s"Lines with a: $numAs, Lines with b: $numBs")
spark.stop()
}
}
I use Spark 2.2.0 and Scala 2.11.7. The pom.xml file is:
<!-- https://mvnrepository.com/artifact/org.apache.spark/spark-core -->
<dependency>
<groupId>org.apache.spark</groupId>
<artifactId>spark-core_2.11</artifactId>
<version>2.2.0</version>
</dependency>
<!-- https://mvnrepository.com/artifact/org.apache.spark/spark-sql -->
<dependency>
<groupId>org.apache.spark</groupId>
<artifactId>spark-sql_2.11</artifactId>
<version>2.2.0</version>
</dependency>
I followed a solution from another thread: NoClassDefFoundError com.apache.hadoop.fs.FSDataInputStream when execute spark-shell
But it doesn't work for me. The content in my spark-env.sh file is:
# If 'hadoop' binary is on your PATH
export SPARK_DIST_CLASSPATH=$(hadoop classpath)
# With explicit path to 'hadoop' binary
export SPARK_DIST_CLASSPATH=$(/usr/local/hadoop/bin/hadoop classpath)
# Passing a Hadoop configuration directory
export SPARK_DIST_CLASSPATH=$(hadoop --config /usr/local/hadoop/etc/hadoop classpath)
Could anybody help me with this? Appreciate your help.
Devesh's answer solve parts of my problem. However, I got other problems:
Using Spark's default log4j profile: org/apache/spark/log4j-defaults.properties
18/08/17 10:34:03 INFO SparkContext: Running Spark version 2.2.0
18/08/17 10:34:03 WARN NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable
18/08/17 10:34:03 WARN Utils: Your hostname, toshiba0 resolves to a loopback address: 127.0.1.1; using 192.168.1.217 instead (on interface wlp2s0)
18/08/17 10:34:03 WARN Utils: Set SPARK_LOCAL_IP if you need to bind to another address
18/08/17 10:34:03 ERROR SparkContext: Error initializing SparkContext.
org.apache.spark.SparkException: A master URL must be set in your configuration
at org.apache.spark.SparkContext.<init>(SparkContext.scala:376)
at org.apache.spark.SparkContext$.getOrCreate(SparkContext.scala:2509)
at org.apache.spark.sql.SparkSession$Builder$$anonfun$6.apply(SparkSession.scala:909)
at org.apache.spark.sql.SparkSession$Builder$$anonfun$6.apply(SparkSession.scala:901)
at scala.Option.getOrElse(Option.scala:121)
at org.apache.spark.sql.SparkSession$Builder.getOrCreate(SparkSession.scala:901)
at com.SimpleApp$.main(SimpleApp.scala:11)
at com.SimpleApp.main(SimpleApp.scala)
18/08/17 10:34:03 INFO SparkContext: Successfully stopped SparkContext
Exception in thread "main" org.apache.spark.SparkException: A master URL must be set in your configuration
at org.apache.spark.SparkContext.<init>(SparkContext.scala:376)
at org.apache.spark.SparkContext$.getOrCreate(SparkContext.scala:2509)
at org.apache.spark.sql.SparkSession$Builder$$anonfun$6.apply(SparkSession.scala:909)
at org.apache.spark.sql.SparkSession$Builder$$anonfun$6.apply(SparkSession.scala:901)
at scala.Option.getOrElse(Option.scala:121)
at org.apache.spark.sql.SparkSession$Builder.getOrCreate(SparkSession.scala:901)
at com.SimpleApp$.main(SimpleApp.scala:11)
at com.SimpleApp.main(SimpleApp.scala)
I don't know why Spark says my loopback address is 127.0.1.1, I checked my configuration: /etc/network/interfaces, it's auto loopback, and I ping 127.0.0.1. It works.
I followed the solution from this link Error initializing SparkContext: A master URL must be set in your configuration
and put the following code, because I use my laptop. It still doesn't work.
val conf = new SparkConf().setMaster("local[2]")
Don't know what happen to my settings. Thank you!

Just add following in maven pom.xml file
<!-- https://mvnrepository.com/artifact/org.apache.hadoop/hadoop-client -->
<dependency>
<groupId>org.apache.hadoop</groupId>
<artifactId>hadoop-client</artifactId>
<version>2.7.0</version>
</dependency>
In previous versions of Spark, you had to create a SparkConf and SparkContext to interact with Spark whereas in Spark 2.0 onwards the same effects can be achieved through SparkSession, without explicitly creating SparkConf, SparkContext or SQLContext, as they’re encapsulated within the SparkSession
** sample code snippet:-**
import org.apache.spark.sql.SparkSession
object SimpleApp {
def main(args: Array[String]) {
val logFile = "YOUR_SPARK_HOME/README.md" // some file on system
val spark = SparkSession
.builder
.appName("Simple Application")
.master("local[2]")
.getOrCreate()
val logData = spark.read.textFile(logFile).cache()
val numAs = logData.filter(line => line.contains("a")).count()
val numBs = logData.filter(line => line.contains("b")).count()
println(s"Lines with a: $numAs, Lines with b: $numBs")
}
}

Related

How to fix "java.lang.reflect.InaccessibleObjectException"

I'm traying to create a simple Spark Session, that read a csv file. But it show me this error :
Exception in thread "main" java.lang.reflect.InaccessibleObjectException: Unable to make field private transient java.lang.String java.net.URI.scheme accessible: module java.base does not "opens java.net" to unnamed module #bcec361
at java.base/java.lang.reflect.AccessibleObject.checkCanSetAccessible(AccessibleObject.java:354)
at java.base/java.lang.reflect.AccessibleObject.checkCanSetAccessible(AccessibleObject.java:297)
at java.base/java.lang.reflect.Field.checkCanSetAccessible(Field.java:178)
at java.base/java.lang.reflect.Field.setAccessible(Field.java:172)
at org.apache.spark.util.SizeEstimator$$anonfun$getClassInfo$3.apply(SizeEstimator.scala:336)
at org.apache.spark.util.SizeEstimator$$anonfun$getClassInfo$3.apply(SizeEstimator.scala:330)
at scala.collection.IndexedSeqOptimized$class.foreach(IndexedSeqOptimized.scala:33)
at scala.collection.mutable.ArrayOps$ofRef.foreach(ArrayOps.scala:186)
at org.apache.spark.util.SizeEstimator$.getClassInfo(SizeEstimator.scala:330)
at org.apache.spark.util.SizeEstimator$.visitSingleObject(SizeEstimator.scala:222)
at org.apache.spark.util.SizeEstimator$.org$apache$spark$util$SizeEstimator$$estimate(SizeEstimator.scala:201)
at org.apache.spark.util.SizeEstimator$.estimate(SizeEstimator.scala:69)
at org.apache.spark.sql.execution.datasources.SharedInMemoryCache$$anon$1.weigh(FileStatusCache.scala:109)
at org.apache.spark.sql.execution.datasources.SharedInMemoryCache$$anon$1.weigh(FileStatusCache.scala:107)
at org.spark_project.guava.cache.LocalCache$Segment.setValue(LocalCache.java:2222)
at org.spark_project.guava.cache.LocalCache$Segment.put(LocalCache.java:2944)
at org.spark_project.guava.cache.LocalCache.put(LocalCache.java:4212)
at org.spark_project.guava.cache.LocalCache$LocalManualCache.put(LocalCache.java:4804)
at org.apache.spark.sql.execution.datasources.SharedInMemoryCache$$anon$3.putLeafFiles(FileStatusCache.scala:152)
at org.apache.spark.sql.execution.datasources.InMemoryFileIndex$$anonfun$listLeafFiles$2.apply(InMemoryFileIndex.scala:130)
at org.apache.spark.sql.execution.datasources.InMemoryFileIndex$$anonfun$listLeafFiles$2.apply(InMemoryFileIndex.scala:128)
at scala.collection.mutable.ResizableArray$class.foreach(ResizableArray.scala:59)
at scala.collection.mutable.ArrayBuffer.foreach(ArrayBuffer.scala:48)
at org.apache.spark.sql.execution.datasources.InMemoryFileIndex.listLeafFiles(InMemoryFileIndex.scala:128)
at org.apache.spark.sql.execution.datasources.InMemoryFileIndex.refresh0(InMemoryFileIndex.scala:91)
at org.apache.spark.sql.execution.datasources.InMemoryFileIndex.<init>(InMemoryFileIndex.scala:67)
at org.apache.spark.sql.execution.datasources.DataSource.org$apache$spark$sql$execution$datasources$DataSource$$createInMemoryFileIndex(DataSource.scala:533)
at org.apache.spark.sql.execution.datasources.DataSource.resolveRelation(DataSource.scala:371)
at org.apache.spark.sql.DataFrameReader.loadV1Source(DataFrameReader.scala:223)
at org.apache.spark.sql.DataFrameReader.load(DataFrameReader.scala:211)
at org.apache.spark.sql.DataFrameReader.text(DataFrameReader.scala:714)
at org.apache.spark.sql.DataFrameReader.text(DataFrameReader.scala:686)
at org.example.SparkSessionTest$.main(SparkSessionTest.scala:19)
at org.example.SparkSessionTest.main(SparkSessionTest.scala)
This is my code :
import org.apache.spark.sql.SparkSession
object SparkSessionTest {
def main(args:Array[String]): Unit ={
val spark = SparkSession.builder()
.master("local[1]")
.appName("SparkByExample")
.getOrCreate();
println("First SparkContext:")
println("APP Name :"+spark.sparkContext.appName);
println("Deploy Mode :"+spark.sparkContext.deployMode);
println("Master :"+spark.sparkContext.master);
val df = spark.read.text("src/data/test.txt")
}
}
I'm using :
jdk-11.0.15.1
scala 2.12.10
spark 3.1.3
And im using Intellij IDE and maven
If you are using intelliJ,
go to file => project structure => Project
check if you have SDK set to 1.8 else download it.

Running Scala Jar with Spark-Submit

I've compiled a spark-scala script to a JAR and I want to run it with spark-submit. But I'm having this error:
2020-01-07 13:03:02,190 WARN util.Utils: Your hostname, nifi resolves to a loopback address: 127.0.1.1; using 10.0.2.15 instead (on interface enp0s3)
2020-01-07 13:03:02,192 WARN util.Utils: Set SPARK_LOCAL_IP if you need to bind to another address
2020-01-07 13:03:03,109 WARN util.NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable
2020-01-07 13:03:03,826 WARN deploy.SparkSubmit$$anon$2: Failed to load hello.
java.lang.ClassNotFoundException: hello
at java.net.URLClassLoader.findClass(URLClassLoader.java:382)
at java.lang.ClassLoader.loadClass(ClassLoader.java:418)
at java.lang.ClassLoader.loadClass(ClassLoader.java:351)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Class.java:348)
at org.apache.spark.util.Utils$.classForName(Utils.scala:238)
at org.apache.spark.deploy.SparkSubmit.org$apache$spark$deploy$SparkSubmit$$runMain(SparkSubmit.scala:806)
at org.apache.spark.deploy.SparkSubmit.doRunMain$1(SparkSubmit.scala:161)
at org.apache.spark.deploy.SparkSubmit.submit(SparkSubmit.scala:184)
at org.apache.spark.deploy.SparkSubmit.doSubmit(SparkSubmit.scala:86)
at org.apache.spark.deploy.SparkSubmit$$anon$2.doSubmit(SparkSubmit.scala:920)
at org.apache.spark.deploy.SparkSubmit$.main(SparkSubmit.scala:929)
at org.apache.spark.deploy.SparkSubmit.main(SparkSubmit.scala)
2020-01-07 13:03:03,857 INFO util.ShutdownHookManager: Shutdown hook called
2020-01-07 13:03:03,858 INFO util.ShutdownHookManager: Deleting directory /tmp/spark-a8cc1ba6-3643-4646-82a3-4b44f4487105
This is my code:
import org.apache.spark.sql.SparkSession
import org.apache.spark.{SparkConf, SparkContext}
object hello {
def main(args: Array[String]): Unit = {
val conf = new SparkConf()
.setMaster("local")
.setAppName("quest9")
val sc = new SparkContext(conf)
val spark = SparkSession.builder().appName("quest9").master("local").getOrCreate()
import spark.implicits._
val zip_codes = spark.read.format("csv").option("header", "true").load("/home/hdfs/Documents/quest_9/doc/zip.csv")
val census = spark.read.format("csv").option("header", "true").load("/home/hdfs/Documents/quest_9/doc/census.csv")
census.createOrReplaceTempView("census")
zip_codes.createOrReplaceTempView("zip")
val query = census.as("census").join((zip_codes.where($"City" === "Inglewood").where($"County" === "Los Angeles").as("zip")),Seq("Zip_Code"),"inner").select($"census.Total_Males".as("male"),$"census.Total_Females".as("female")).distinct()
query.show()
val queryR = query.repartition(5)
queryR.write.parquet("/home/hdfs/Documents/population/census/IDE/census.parquet")
sc.stop()
}
}
I think my problem is that im using scala object instead of a class, but I'm not sure.
I run the spark-submit like this
spark-submit \
--class hello \
/home/hdfs/IdeaProjects/untitled/out/artifacts/quest_jar/quest.jar
Anyone solved this error before?
I think you need to specify a package name for both spark-submit and your object.
For instance :
spark-submit \
--class com.my.package.hello \
/home/hdfs/IdeaProjects/untitled/out/artifacts/quest_jar/quest.jar
and
package com.my.package
import org.apache.spark.sql.SparkSession
import org.apache.spark.{SparkConf, SparkContext}
object hello {
...
}

ClassNotFoundException in SparkStreaming Example

I am new to Spark streaming and trying to run a example from this tutorial and I am following MAKING AND RUNNING OUR OWN NETWORKWORDCOUNT.
I have completed 8th step and made a jar from sbt.
Now I am trying to run deploy my jar using the command in 9th step like this:
bin/spark-submit --class "NetworkWordCount" --master spark://abc:7077 target/scala-2.11/networkcount_2.11-1.0.jar localhost 9999
but when I run this command I get following exception:
java.lang.ClassNotFoundException: NetworkWordCount
at java.net.URLClassLoader.findClass(URLClassLoader.java:381) at
java.lang.ClassLoader.loadClass(ClassLoader.java:424) at
java.lang.ClassLoader.loadClass(ClassLoader.java:357) at
java.lang.Class.forName0(Native Method) at
java.lang.Class.forName(Class.java:348) at
org.apache.spark.util.Utils$.classForName(Utils.scala:229) at
org.apache.spark.deploy.SparkSubmit$.org$apache$spark$deploy$SparkSubmit$$runMain(SparkSubmit.scala:700)
at
org.apache.spark.deploy.SparkSubmit$.doRunMain$1(SparkSubmit.scala:187)
at org.apache.spark.deploy.SparkSubmit$.submit(SparkSubmit.scala:212)
at org.apache.spark.deploy.SparkSubmit$.main(SparkSubmit.scala:126)
at org.apache.spark.deploy.SparkSubmit.main(SparkSubmit.scala)
jar that I have created contains "NetworkWordCount" class having the following code from the spark examples
package src.main.scala
import org.apache.spark.SparkConf
import org.apache.spark.storage.StorageLevel
import org.apache.spark.streaming.{Seconds, StreamingContext}
object NetworkWordCount {
def main(args: Array[String]) {
if (args.length < 2) {
System.err.println("Usage: NetworkWordCount <hostname> <port>")
System.exit(1)
}
//StreamingExamples.setStreamingLogLevels()
// Create the context with a 1 second batch size
val sparkConf = new SparkConf().setAppName("MyNetworkWordCount")
val ssc = new StreamingContext(sparkConf, Seconds(1))
val lines = ssc.socketTextStream(args(0), args(1).toInt, StorageLevel.MEMORY_AND_DISK_SER)
val words = lines.flatMap(_.split(" "))
val wordCounts = words.map(x => (x, 1)).reduceByKey(_ + _)
wordCounts.print()
ssc.start()
ssc.awaitTermination()
}
}
I am unable to identify what am I doing wrong.
The spark-submit parameter --class takes a fully qualified class name.
In the case of the code above, it should be src.main.scala.NetworkCount
bin/spark-submit --class src.main.scala.NetworkCount --master spark://abc:7077 target/scala-2.11/networkcount_2.11-1.0.jar localhost 9999
Note: the package name used looks like an IDE setup issue. src/main/scala is the typical root for a scala code base, and not a package name.
make sure you have the "target/scala-2.11/networkcount_2.11-1.0.jar" file in your current dir when executing spark-submit

Running first program in Spark

I am trying to run my first program in Spark with scala. Trying to read a csv file and display.
Code:
import org.apache.spark.sql.SparkSession
import org.apache.spark._
import java.io._
import org.apache.spark.SparkContext._
import org.apache.log4j._
object df extends App{
val spark=SparkSession.builder().getOrCreate()
val drf=spark.read.csv("C:/Users/admin/Desktop/scala-datasets/Scala-and-
Spark-Bootcamp-master/Spark DataFrames/CitiGroup2006_2008")
drf.head(5)
}
Getting the following error:
Using Spark's default log4j profile: org/apache/spark/log4j-defaults.properties
17/04/29 23:10:53 INFO SparkContext: Running Spark version 2.1.0
17/04/29 23:10:56 WARN NativeCodeLoader: Unable to load native-hadoop
library for your platform... using builtin-java classes where applicable
17/04/29 23:10:57 ERROR SparkContext: Error initializing SparkContext.
org.apache.spark.SparkException: A master URL must be set in your
configuration at org.apache.spark.SparkContext.<init>
(SparkContext.scala:379)
at org.apache.spark.SparkContext$.getOrCreate(SparkContext.scala:2313)
at org.apache.spark.sql.SparkSession$Builder$$anonfun$6.apply(SparkSession.scala:868)
at org.apache.spark.sql.SparkSession$Builder$$anonfun$6.apply(SparkSession.scala:860)
at scala.Option.getOrElse(Option.scala:121)
at org.apache.spark.sql.SparkSession$Builder.getOrCreate(SparkSession.scala:860)
at df$.delayedEndpoint$df$1(df.scala:11)
at df$delayedInit$body.apply(df.scala:9)
at scala.Function0$class.apply$mcV$sp(Function0.scala:34)
at scala.runtime.AbstractFunction0.apply$mcV$sp(AbstractFunction0.scala:12)
at scala.App$$anonfun$main$1.apply(App.scala:76)
at scala.App$$anonfun$main$1.apply(App.scala:76)
at scala.collection.immutable.List.foreach(List.scala:381)
at scala.collection.generic.TraversableForwarder$class.foreach(TraversableForwarder.scala:35)
at scala.App$class.main(App.scala:76)
at df$.main(df.scala:9)
at df.main(df.scala)
Any suggestions would be helpful
You missed .master() function call. for example if you want to run in local mode following is the solution :
object df extends App{
val spark=SparkSession.builder().master("local").getOrCreate()
val drf=spark.read.csv("C:/Users/admin/Desktop/scala-datasets/Scala-and-
Spark-Bootcamp-master/Spark DataFrames/CitiGroup2006_2008")
drf.head(5)
}
And the error log clearly says that
17/04/29 23:10:57 ERROR SparkContext: Error initializing SparkContext.
org.apache.spark.SparkException: A master URL must be set in your
configuration at org.apache.spark.SparkContext.<init>
(SparkContext.scala:379)
Hope it helps
As previous comment said you should setup master for your spark context, in your case it should be local[1] or local[*]. Also you should set a appName.
You can avoid master and appName specification via code using spark-submit with keys.
import org.apache.spark.sql.SparkSession
object df extends App{
override def main(args: Array[String]): Unit = {
val spark = SparkSession.builder().appName("example").master("local[*]").getOrCreate()
val drf = spark.read.csv("C:/Users/admin/Desktop/scala-datasets/Scala-and-Spark-Bootcamp-master/Spark DataFrames/CitiGroup2006_2008")
drf.head(5)
}
}

ERROR Utils: Uncaught exception in thread SparkListenerBus

I try to execute simple project with Apache Spark. This is my code SimpleApp.scala
/* SimpleApp.scala */
import org.apache.spark.SparkContext
import org.apache.spark.SparkContext._
import org.apache.spark.SparkConf
object SimpleApp {
def main(args: Array[String]) {
val logFile = "/home/hduser/spark-1.2.0-bin-hadoop2.4/README.md" // Should be some file on your system
// val conf = new SparkConf().setAppName("Simple Application")
val sc = new SparkContext("local", "Simple Job", "/home/hduser/spark-1.2.0-bin-hadoop2.4/")
val logData = sc.textFile(logFile, 2).cache()
val numAs = logData.filter(line => line.contains("hadoop")).count()
val numBs = logData.filter(line => line.contains("see")).count()
println("Lines with hadoop: %s, Lines with see: %s".format(numAs, numBs))
}
}
when I manually send this job to Spark with command line : /home/hduser/spark-1.2.0-hadoop-2.4.0/bin/spark-submit --class "SimpleApp" --master local[4] target/scala-2.10/simple-project_2.10-1.0.jar it's run successfully.
if I run with sbt run and with the service apache spark is running, it's success, but in the end of log it give error like this :
15/02/06 15:56:49 ERROR Utils: Uncaught exception in thread SparkListenerBus
java.lang.InterruptedException
at java.util.concurrent.locks.AbstractQueuedSynchronizer.doAcquireSharedInterruptibly(AbstractQueuedSynchronizer.java:996)
at java.util.concurrent.locks.AbstractQueuedSynchronizer.acquireSharedInterruptibly(AbstractQueuedSynchronizer.java:1303)
at java.util.concurrent.Semaphore.acquire(Semaphore.java:317)
at org.apache.spark.scheduler.LiveListenerBus$$anon$1$$anonfun$run$1.apply$mcV$sp(LiveListenerBus.scala:48)
at org.apache.spark.scheduler.LiveListenerBus$$anon$1$$anonfun$run$1.apply(LiveListenerBus.scala:47)
at org.apache.spark.scheduler.LiveListenerBus$$anon$1$$anonfun$run$1.apply(LiveListenerBus.scala:47)
at org.apache.spark.util.Utils$.logUncaughtExceptions(Utils.scala:1460)
at org.apache.spark.scheduler.LiveListenerBus$$anon$1.run(LiveListenerBus.scala:46)
15/02/06 15:56:49 ERROR ContextCleaner: Error in cleaning thread
java.lang.InterruptedException
at java.lang.Object.wait(Native Method)
at java.lang.ref.ReferenceQueue.remove(ReferenceQueue.java:135)
at org.apache.spark.ContextCleaner$$anonfun$org$apache$spark$ContextCleaner$$keepCleaning$1.apply$mcV$sp(ContextCleaner.scala:136)
at org.apache.spark.ContextCleaner$$anonfun$org$apache$spark$ContextCleaner$$keepCleaning$1.apply(ContextCleaner.scala:134)
at org.apache.spark.ContextCleaner$$anonfun$org$apache$spark$ContextCleaner$$keepCleaning$1.apply(ContextCleaner.scala:134)
at org.apache.spark.util.Utils$.logUncaughtExceptions(Utils.scala:1460)
at org.apache.spark.ContextCleaner.org$apache$spark$ContextCleaner$$keepCleaning(ContextCleaner.scala:133)
at org.apache.spark.ContextCleaner$$anon$3.run(ContextCleaner.scala:65)
Any wrong in my code? Thanks in advance.
I use apache spark 1.2.0-bin-hadoop-2.4, scala 2.10.4
The SparkContext or SparkSession (Spark >= 2.0.0) should be stopped when the Spark code is run by adding sc.stop or spark.stop (Spark >= 2.0.0) at the end of the code.
According this mail archive, i.e.:
Hi Haoming,
You can safely disregard this error. This is printed at the end of the
execution when we clean up and kill the daemon context cleaning
thread. In the future it would be good to silence this particular
message, as it may be confusing to users.
Andrew
the error could be disregarded.