Apache Spark Exception in thread "main" java.lang.NoClassDefFoundError: scala/collection/GenTraversableOnce$class

Question

Scala version:2.11.7(had to upgrade the scala verison to enable case clasess to accept more than 22 parameters.) Spark version:1.6.1 PFB pom.xml

Getting below error when trying to setup spark on intellij IDE,

16/03/16 18:36:44 INFO spark.SparkContext: Running Spark version 1.6.1
Exception in thread "main" java.lang.NoClassDefFoundError: scala/collection/GenTraversableOnce$class
    at org.apache.spark.util.TimeStampedWeakValueHashMap.<init>(TimeStampedWeakValueHashMap.scala:42)
    at org.apache.spark.SparkContext.<init>(SparkContext.scala:298)
    at com.examples.testSparkPost$.main(testSparkPost.scala:27)
    at com.examples.testSparkPost.main(testSparkPost.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 com.intellij.rt.execution.application.AppMain.main(AppMain.java:140)
Caused by: java.lang.ClassNotFoundException: scala.collection.GenTraversableOnce$class
    at java.net.URLClassLoader$1.run(URLClassLoader.java:366)
    at java.net.URLClassLoader$1.run(URLClassLoader.java:355)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.net.URLClassLoader.findClass(URLClassLoader.java:354)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:425)
    at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:308)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:358)
    ... 9 more

pom.xml:

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
     xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>StreamProcess</groupId>
<artifactId>StreamProcess</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>${project.artifactId}</name>
<description>This is a boilerplate maven project to start using Spark in Scala</description>
<inceptionYear>2010</inceptionYear>

<properties>
    <maven.compiler.source>1.6</maven.compiler.source>
    <maven.compiler.target>1.6</maven.compiler.target>
    <encoding>UTF-8</encoding>
    <scala.tools.version>2.10</scala.tools.version>
    <!-- Put the Scala version of the cluster -->
    <scala.version>2.11.7</scala.version>
</properties>

<!-- repository to add org.apache.spark -->
<repositories>
    <repository>
        <id>cloudera-repo-releases</id>
        <url>https://repository.cloudera.com/artifactory/repo/</url>
    </repository>
</repositories>

<build>
    <sourceDirectory>src/main/scala</sourceDirectory>
    <testSourceDirectory>src/test/scala</testSourceDirectory>
    <plugins>
            <!-- any other plugins -->
            <plugin>
                <artifactId>maven-assembly-plugin</artifactId>
                <executions>
                    <execution>
                        <phase>package</phase>
                        <goals>
                            <goal>single</goal>
                        </goals>
                    </execution>
                </executions>
                <configuration>
                    <descriptorRefs>
                        <descriptorRef>jar-with-dependencies</descriptorRef>
                    </descriptorRefs>
                </configuration>
            </plugin>
        <plugin>
            <!-- see http://davidb.github.com/scala-maven-plugin -->
            <groupId>net.alchim31.maven</groupId>
            <artifactId>scala-maven-plugin</artifactId>
            <version>3.2.2</version>
            <executions>
                <execution>
                    <goals>
                        <goal>compile</goal>
                        <goal>testCompile</goal>
                    </goals>
                    <configuration>
                        <args>
                            <!--<arg>-make:transitive</arg>-->
                            <arg>-dependencyfile</arg>
                            <arg>${project.build.directory}/.scala_dependencies</arg>
                        </args>
                    </configuration>
                </execution>
            </executions>
        </plugin>

        <!-- "package" command plugin -->
        <plugin>
            <artifactId>maven-assembly-plugin</artifactId>
            <version>2.4.1</version>
            <configuration>
                <descriptorRefs>
                    <descriptorRef>jar-with-dependencies</descriptorRef>
                </descriptorRefs>
            </configuration>
            <executions>
                <execution>
                    <id>make-assembly</id>
                    <phase>package</phase>
                    <goals>
                        <goal>single</goal>
                    </goals>
                </execution>
            </executions>
        </plugin>
    </plugins>
</build>
<dependencies>
    <dependency>
        <groupId>org.scala-lang</groupId>
        <artifactId>scala-library</artifactId>
        <version>${scala.version}</version>
    </dependency>
    <dependency>
        <groupId>org.mongodb.mongo-hadoop</groupId>
        <artifactId>mongo-hadoop-core</artifactId>
        <version>1.4.2</version>
        <exclusions>
            <exclusion>
                <groupId>javax.servlet</groupId>
                <artifactId>servlet-api</artifactId>
            </exclusion>
        </exclusions>
    </dependency>
    <dependency>
            <groupId>org.mongodb</groupId>
            <artifactId>mongodb-driver</artifactId>
            <version>3.2.2</version>
        <exclusions>
            <exclusion>
                <groupId>javax.servlet</groupId>
                <artifactId>servlet-api</artifactId>
            </exclusion>
        </exclusions>
    </dependency>
    <dependency>
            <groupId>org.mongodb</groupId>
            <artifactId>mongodb-driver</artifactId>
            <version>3.2.2</version>
        <exclusions>
            <exclusion>
                <groupId>javax.servlet</groupId>
                <artifactId>servlet-api</artifactId>
            </exclusion>
        </exclusions>
        </dependency>
    <dependency>
        <groupId>org.apache.spark</groupId>
        <artifactId>spark-streaming_2.10</artifactId>
        <version>1.6.1</version>
    </dependency>
    <dependency>
        <groupId>org.apache.spark</groupId>
        <artifactId>spark-core_2.10</artifactId>
        <version>1.6.1</version>
    </dependency>
    <dependency>
        <groupId>org.apache.spark</groupId>
        <artifactId>spark-sql_2.10</artifactId>
        <version>1.6.1</version>
    </dependency>
    <dependency>
        <groupId>org.apache.hadoop</groupId>
        <artifactId>hadoop-hdfs</artifactId>
        <version>2.6.0</version>
    </dependency>
    <dependency>
        <groupId>org.apache.hadoop</groupId>
        <artifactId>hadoop-auth</artifactId>
        <version>2.6.0</version>
    </dependency>
    <dependency>
        <groupId>org.apache.hadoop</groupId>
        <artifactId>hadoop-common</artifactId>
        <version>2.6.0</version>
    </dependency>
    <dependency>
        <groupId>org.apache.hadoop</groupId>
        <artifactId>hadoop-core</artifactId>
        <version>1.2.1</version>
    </dependency>
</dependencies>

Would like to know , what to be changed in pom to get things going.

Answer 1

In the POM you have Scala version 2.11.7 but later on in the dependencies you are declaring Spark deps compiled against 2.10:

<artifactId>spark-streaming_2.10</artifactId>
<artifactId>spark-core_2.10</artifactId>
<artifactId>spark-sql_2.10</artifactId>

You have to change it to:

<artifactId>spark-streaming_2.11</artifactId>
<artifactId>spark-core_2.11</artifactId>
<artifactId>spark-sql_2.11</artifactId>