How to fix java.lang.ClassCastException: cannot assign instance of scala.collection.immutable.List to field type scala.collection.Seq?
<p>This error has been the hardest to trace. I am not sure what is going on. I am running a Spark cluster on my location machine. so the entire spark cluster is under one host which is <code>127.0.0.1</code> and I run on a standalone mode   </p>

<pre><code>JavaPairRDD&lt;byte[], Iterable&lt;CassandraRow&gt;&gt; cassandraRowsRDD= javaFunctions(sc).cassandraTable("test", "hello" )
   .select("rowkey", "col1", "col2", "col3",  )
   .spanBy(new Function&lt;CassandraRow, byte[]&gt;() {
        @Override
        public byte[] call(CassandraRow v1) {
            return v1.getBytes("rowkey").array();
        }
    }, byte[].class);

Iterable&lt;Tuple2&lt;byte[], Iterable&lt;CassandraRow&gt;&gt;&gt; listOftuples = cassandraRowsRDD.collect(); //ERROR HAPPENS HERE
Tuple2&lt;byte[], Iterable&lt;CassandraRow&gt;&gt; tuple = listOftuples.iterator().next();
byte[] partitionKey = tuple._1();
for(CassandraRow cassandraRow: tuple._2()) {
    System.out.println("************START************");
    System.out.println(new String(partitionKey));
    System.out.println("************END************");
}
</code></pre>

<p>This error has been the hardest to trace. It clearly happens at <code>cassandraRowsRDD.collect()</code> and I dont know why?</p>

<pre><code>16/10/09 23:36:21 ERROR Executor: Exception in task 2.3 in stage 0.0 (TID 21)
java.lang.ClassCastException: cannot assign instance of scala.collection.immutable.List$SerializationProxy to field org.apache.spark.rdd.RDD.org$apache$spark$rdd$RDD$$dependencies_ of type scala.collection.Seq in instance of org.apache.spark.rdd.MapPartitionsRDD
    at java.io.ObjectStreamClass$FieldReflector.setObjFieldValues(ObjectStreamClass.java:2133)
    at java.io.ObjectStreamClass.setObjFieldValues(ObjectStreamClass.java:1305)
    at java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:2006)
    at java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1924)
    at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1801)
    at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1351)
    at java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:2000)
    at java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1924)
    at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1801)
    at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1351)
    at java.io.ObjectInputStream.readObject(ObjectInputStream.java:371)
    at org.apache.spark.serializer.JavaDeserializationStream.readObject(JavaSerializer.scala:75)
    at org.apache.spark.serializer.JavaSerializerInstance.deserialize(JavaSerializer.scala:114)
    at org.apache.spark.scheduler.ResultTask.runTask(ResultTask.scala:66)
    at org.apache.spark.scheduler.Task.run(Task.scala:85)
    at org.apache.spark.executor.Executor$TaskRunner.run(Executor.scala:274)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
    at java.lang.Thread.run(Thread.java:745)
</code></pre>

<p>Here are the versions I use</p>

<pre><code>Scala code runner version 2.11.8  // when I run scala -version or even ./spark-shell


compile group: 'org.apache.spark' name: 'spark-core_2.11' version: '2.0.0'
compile group: 'org.apache.spark' name: 'spark-streaming_2.11' version: '2.0.0'
compile group: 'org.apache.spark' name: 'spark-sql_2.11' version: '2.0.0'
compile group: 'com.datastax.spark' name: 'spark-cassandra-connector_2.11' version: '2.0.0-M3': 
</code></pre>

<p>my gradle file looks like this after introducing something called "provided" which actually doesn't seem to exist but google said to create one so my build.gradle looks like this</p>

<pre><code>group 'com.company'
version '1.0-SNAPSHOT'

apply plugin: 'java'
apply plugin: 'idea'

repositories {
    mavenCentral()
    mavenLocal()
}

configurations {
    provided
}
sourceSets {
    main {
        compileClasspath += configurations.provided
        test.compileClasspath += configurations.provided
        test.runtimeClasspath += configurations.provided
    }
}

idea {
    module {
        scopes.PROVIDED.plus += [ configurations.provided ]
    }
}

dependencies {
    compile 'org.slf4j:slf4j-log4j12:1.7.12'
    provided group: 'org.apache.spark', name: 'spark-core_2.11', version: '2.0.0'
    provided group: 'org.apache.spark', name: 'spark-streaming_2.11', version: '2.0.0'
    provided group: 'org.apache.spark', name: 'spark-sql_2.11', version: '2.0.0'
    provided group: 'com.datastax.spark', name: 'spark-cassandra-connector_2.11', version: '2.0.0-M3'
}



jar {
    from { configurations.provided.collect { it.isDirectory() ? it : zipTree(it) } }
   // with jar
    from sourceSets.test.output
    manifest {
        attributes 'Main-Class': "com.company.batchprocessing.Hello"
    }
    exclude 'META-INF/.RSA', 'META-INF/.SF', 'META-INF/*.DSA'
    zip64 true
}
</code></pre>