Apache Spark 1.5与Cassandra：类强制转换异常

我使用以下软件：

Cassandra 2.1.9 Spark 1.5 Java使用Datastax提供的Cassandra驱动程序 . Ubuntu 12.0.4

当我使用 local[8] 在本地运行spark时，程序运行正常，数据保存到Cassandra中 . 但是，当我将作业提交到spark集群时，会抛出以下异常：

16 Sep 2015 03:08:58,808  WARN [task-result-getter-0] (Logging.scala:71) TaskSetManager - Lost task 3.0 in stage 0.0 (TID 3,
192.168.50.131): java.lang.ClassCastException: cannot assign instance of scala.collection.immutable.HashMap$SerializationProxy to field scala.collection.Map$WithDefault.underlying of type scala.collection.Map in instance of scala.collection.immutable.Map$WithDefault
        at java.io.ObjectStreamClass$FieldReflector.setObjFieldValues(ObjectStreamClass.java:2083)
        at java.io.ObjectStreamClass.setObjFieldValues(ObjectStreamClass.java:1261)
        at java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:1996)
        at java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1915)
        at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1798)
        at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1350)
        at java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:1990)
        at java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1915)
        at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1798)
        at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1350)
        at java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:1990)
        at java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1915)
        at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1798)
        at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1350)
        at java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:1990)
        at java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1915)
        at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1798)
        at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1350)
        at java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:1990)
        at java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1915)
        at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1798)
        at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1350)
        at java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:1990)
        at java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1915)
        at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1798)
        at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1350)
        at java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:1990)
        at java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1915)
        at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1798)
        at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1350)
        at java.io.ObjectInputStream.readObject(ObjectInputStream.java:370)
        at org.apache.spark.serializer.JavaDeserializationStream.readObject(JavaSerializer.scala:72)
        at org.apache.spark.serializer.JavaSerializerInstance.deserialize(JavaSerializer.scala:98)
        at org.apache.spark.scheduler.ResultTask.runTask(ResultTask.scala:61)
        at org.apache.spark.scheduler.Task.run(Task.scala:88)
        at org.apache.spark.executor.Executor$TaskRunner.run(Executor.scala:214)
        at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
        at java.lang.Thread.run(Thread.java:745)

我不知道如何解决这个错误 . 我只使用以下2个依赖项：

spark-assembly-1.5.0-hadoop2.6.0.jar - >附带Spark下载spark-cassandra-connector-java-assembly-1.5.0-M1-SNAPSHOT.jar - >使用sbt从Git构建 .

我已将捆绑的应用程序jar导出到spark类路径中 . 请帮忙，因为我不确定这是特定于应用程序的错误还是Spark发布本身的问题 .