I am getting this error when I am trying to create rdd of (protokey, value). When I change this to (*protokey.toString*, value) it works fine.
*This is the stack trace:* java.lang.RuntimeException: Unable to find proto buffer class at com.google.protobuf.GeneratedMessageLite$SerializedForm.readResolve(GeneratedMessageLite.java:775) at sun.reflect.GeneratedMethodAccessor26.invoke(Unknown Source) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:606) at java.io.ObjectStreamClass.invokeReadResolve(ObjectStreamClass.java:1104) at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1807) 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:76) at org.apache.spark.serializer.DeserializationStream.readKey(Serializer.scala:169) at org.apache.spark.serializer.DeserializationStream$$anon$2.getNext(Serializer.scala:201) at org.apache.spark.serializer.DeserializationStream$$anon$2.getNext(Serializer.scala:198) at org.apache.spark.util.NextIterator.hasNext(NextIterator.scala:73) at scala.collection.Iterator$$anon$13.hasNext(Iterator.scala:371) at scala.collection.Iterator$$anon$11.hasNext(Iterator.scala:327) at org.apache.spark.util.CompletionIterator.hasNext(CompletionIterator.scala:32) at org.apache.spark.InterruptibleIterator.hasNext(InterruptibleIterator.scala:39) at org.apache.spark.util.collection.ExternalAppendOnlyMap.insertAll(ExternalAppendOnlyMap.scala:152) at org.apache.spark.Aggregator.combineCombinersByKey(Aggregator.scala:58) at org.apache.spark.shuffle.BlockStoreShuffleReader.read(BlockStoreShuffleReader.scala:83) at org.apache.spark.rdd.ShuffledRDD.compute(ShuffledRDD.scala:98) at org.apache.spark.rdd.RDD.computeOrReadCheckpoint(RDD.scala:306) at org.apache.spark.rdd.RDD.iterator(RDD.scala:270) at org.apache.spark.scheduler.ResultTask.runTask(ResultTask.scala:66) at org.apache.spark.scheduler.Task.run(Task.scala:89) at org.apache.spark.executor.Executor$TaskRunner.run(Executor.scala:214) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615) at java.lang.Thread.run(Thread.java:745) *Caused by: java.lang.ClassNotFoundException: com.rocketfuel.common.message.protobuf.generated.ApolloProtos$ApolloMvKey* 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) at java.lang.Class.forName0(Native Method) at java.lang.Class.forName(Class.java:190) at com.google.protobuf.GeneratedMessageLite$SerializedForm.readResolve(GeneratedMessageLite.java:768) ... 28 more The class has been packaged into the jar and also doing *.toString* works fine. Does anyone has any idea on this? Thanks Nikhil