title: java.lang.ClassCastException and java.lang.AssertionError while running nodetool cleanup
body: <p>I am using cassandra-2.0.3, I have added a new node in datacenter (using vnodes) but while running nodetool cleanup i am getting </p>
  
  <pre><code>Error occurred during cleanup
  java.util.concurrent.ExecutionException: java.lang.ClassCastException: org.apache.cassandra.io.sstable.SSTableReader$EmptyCompactionScanner cannot be cast to org.apache.cassandra.io.sstable.SSTableScanner
      at java.util.concurrent.FutureTask.report(FutureTask.java:122)
      at java.util.concurrent.FutureTask.get(FutureTask.java:188)
      at org.apache.cassandra.db.compaction.CompactionManager.performAllSSTableOperation(CompactionManager.java:227)
      at org.apache.cassandra.db.compaction.CompactionManager.performCleanup(CompactionManager.java:265)
      at org.apache.cassandra.db.ColumnFamilyStore.forceCleanup(ColumnFamilyStore.java:1054)
      at org.apache.cassandra.service.StorageService.forceKeyspaceCleanup(StorageService.java:2038)
      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 sun.reflect.misc.Trampoline.invoke(MethodUtil.java:75)
      at sun.reflect.GeneratedMethodAccessor8.invoke(Unknown Source)
      at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
      at java.lang.reflect.Method.invoke(Method.java:606)
      at sun.reflect.misc.MethodUtil.invoke(MethodUtil.java:279)
      at com.sun.jmx.mbeanserver.StandardMBeanIntrospector.invokeM2(StandardMBeanIntrospector.java:112)
      at com.sun.jmx.mbeanserver.StandardMBeanIntrospector.invokeM2(StandardMBeanIntrospector.java:46)
      at com.sun.jmx.mbeanserver.MBeanIntrospector.invokeM(MBeanIntrospector.java:237)
      at com.sun.jmx.mbeanserver.PerInterface.invoke(PerInterface.java:138)
      at com.sun.jmx.mbeanserver.MBeanSupport.invoke(MBeanSupport.java:252)
      at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.invoke(DefaultMBeanServerInterceptor.java:819)
      at com.sun.jmx.mbeanserver.JmxMBeanServer.invoke(JmxMBeanServer.java:801)
      at javax.management.remote.rmi.RMIConnectionImpl.doOperation(RMIConnectionImpl.java:1487)
      at javax.management.remote.rmi.RMIConnectionImpl.access$300(RMIConnectionImpl.java:97)
      at javax.management.remote.rmi.RMIConnectionImpl$PrivilegedOperation.run(RMIConnectionImpl.java:1328)
      at javax.management.remote.rmi.RMIConnectionImpl.doPrivilegedOperation(RMIConnectionImpl.java:1420)
      at javax.management.remote.rmi.RMIConnectionImpl.invoke(RMIConnectionImpl.java:848)
      at sun.reflect.GeneratedMethodAccessor23.invoke(Unknown Source)
      at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
      at java.lang.reflect.Method.invoke(Method.java:606)
      at sun.rmi.server.UnicastServerRef.dispatch(UnicastServerRef.java:322)
      at sun.rmi.transport.Transport$1.run(Transport.java:177)
      at sun.rmi.transport.Transport$1.run(Transport.java:174)
      at java.security.AccessController.doPrivileged(Native Method)
      at sun.rmi.transport.Transport.serviceCall(Transport.java:173)
      at sun.rmi.transport.tcp.TCPTransport.handleMessages(TCPTransport.java:556)
      at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run0(TCPTransport.java:811)
      at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run(TCPTransport.java:670)
      at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
      at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
      at java.lang.Thread.run(Thread.java:744)
  Caused by: java.lang.ClassCastException: org.apache.cassandra.io.sstable.SSTableReader$EmptyCompactionScanner cannot be cast to org.apache.cassandra.io.sstable.SSTableScanner
      at org.apache.cassandra.db.compaction.CompactionManager.doCleanupCompaction(CompactionManager.java:563)
      at org.apache.cassandra.db.compaction.CompactionManager.access$400(CompactionManager.java:62)
      at org.apache.cassandra.db.compaction.CompactionManager$5.perform(CompactionManager.java:274)
      at org.apache.cassandra.db.compaction.CompactionManager$2.call(CompactionManager.java:222)
      at java.util.concurrent.FutureTask.run(FutureTask.java:262)
      ... 3 more
  </code></pre>
  
  <p>After some time I tried it to run again and its end up with java.lang.AssertionError.</p>
  
  <pre><code>Exception in thread "main" java.lang.AssertionError: [SSTableReader(path='/home/test/cassandra/data/Emails-jb-6-Data.db'), SSTableReader(path='/home/test/cassandra/data/Emails-jb-5-Data.db'), SSTableReader(path='/home/test/cassandra/data/Emails-jb-4-Data.db')]
  at org.apache.cassandra.db.ColumnFamilyStore$12.call(ColumnFamilyStore.java:2054)
  at org.apache.cassandra.db.ColumnFamilyStore$12.call(ColumnFamilyStore.java:2051)
  at org.apache.cassandra.db.ColumnFamilyStore.runWithCompactionsDisabled(ColumnFamilyStore.java:2033)
  at org.apache.cassandra.db.ColumnFamilyStore.markAllCompacting(ColumnFamilyStore.java:2064)
  at org.apache.cassandra.db.compaction.CompactionManager.performAllSSTableOperation(CompactionManager.java:214)
  at org.apache.cassandra.db.compaction.CompactionManager.performCleanup(CompactionManager.java:265)
  at org.apache.cassandra.db.ColumnFamilyStore.forceCleanup(ColumnFamilyStore.java:1054)
  at org.apache.cassandra.service.StorageService.forceKeyspaceCleanup(StorageService.java:2038)
  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 sun.reflect.misc.Trampoline.invoke(MethodUtil.java:75)
  at sun.reflect.GeneratedMethodAccessor8.invoke(Unknown Source)
  at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
  at java.lang.reflect.Method.invoke(Method.java:606)
  at sun.reflect.misc.MethodUtil.invoke(MethodUtil.java:279)
  at com.sun.jmx.mbeanserver.StandardMBeanIntrospector.invokeM2(StandardMBeanIntrospector.java:112)
  at com.sun.jmx.mbeanserver.StandardMBeanIntrospector.invokeM2(StandardMBeanIntrospector.java:46)
  at com.sun.jmx.mbeanserver.MBeanIntrospector.invokeM(MBeanIntrospector.java:237)
  at com.sun.jmx.mbeanserver.PerInterface.invoke(PerInterface.java:138)
  at com.sun.jmx.mbeanserver.MBeanSupport.invoke(MBeanSupport.java:252)
  at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.invoke(DefaultMBeanServerInterceptor.java:819)
  at com.sun.jmx.mbeanserver.JmxMBeanServer.invoke(JmxMBeanServer.java:801)
  at javax.management.remote.rmi.RMIConnectionImpl.doOperation(RMIConnectionImpl.java:1487)
  at javax.management.remote.rmi.RMIConnectionImpl.access$300(RMIConnectionImpl.java:97)
  at javax.management.remote.rmi.RMIConnectionImpl$PrivilegedOperation.run(RMIConnectionImpl.java:1328)
  at javax.management.remote.rmi.RMIConnectionImpl.doPrivilegedOperation(RMIConnectionImpl.java:1420)
  at javax.management.remote.rmi.RMIConnectionImpl.invoke(RMIConnectionImpl.java:848)
  at sun.reflect.GeneratedMethodAccessor12.invoke(Unknown Source)
  at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
  at java.lang.reflect.Method.invoke(Method.java:606)
  at sun.rmi.server.UnicastServerRef.dispatch(UnicastServerRef.java:322)
  at sun.rmi.transport.Transport$1.run(Transport.java:177)
  at sun.rmi.transport.Transport$1.run(Transport.java:174)
  at java.security.AccessController.doPrivileged(Native Method)
  at sun.rmi.transport.Transport.serviceCall(Transport.java:173)
  at sun.rmi.transport.tcp.TCPTransport.handleMessages(TCPTransport.java:556)
  at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run0(TCPTransport.java:811)
  at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run(TCPTransport.java:670)
  at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
  at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
  at java.lang.Thread.run(Thread.java:744)
  </code></pre>
  
  <p>what are the cause for the above exceptions? Any quick solutions?</p>