E. Sammer created KAFKA-2284: -------------------------------- Summary: ConsumerRebalanceListener receives wrong type in partitionOwnership values Key: KAFKA-2284 URL: https://issues.apache.org/jira/browse/KAFKA-2284 Project: Kafka Issue Type: Bug Components: consumer Affects Versions: 0.8.2.0 Reporter: E. Sammer Assignee: Neha Narkhede Priority: Blocker
The ConsumerRebalanceListener's beforeReleasingPartitions() method is supposed to receive an arg of Map<String, Set<Integer>> (topic -> Set(partitions)). Even though the type of the map value is specified as a java.util.Set, a scala.collection.convert.Wrappers$JSetWrapper is passed instead which does not implement Set<T> causing a class cast exception as soon as one attempts to access any value of the map. It looks as if this method was never tested against the actual types specified by the interface. Here's what happens if you call {{Set<T> foo = partitionOwnership.get(topic)}}: {code} 2015-06-18 07:28:43,776 (search-consumer_esammer-mbp.local-1434637723383-12126c1b_watcher_executor) [WARN - com.rocana.search.consumer.ConsumerService$1.beforeReleasingPartitions(ConsumerService.java:246)] Exception while rebalancing! java.lang.ClassCastException: scala.collection.convert.Wrappers$JSetWrapper cannot be cast to java.util.Set at com.rocana.search.consumer.IndexConsumerWorker.onRebalance(IndexConsumerWorker.java:80) at com.rocana.search.consumer.ConsumerService$1.beforeReleasingPartitions(ConsumerService.java:244) at kafka.consumer.ZookeeperConsumerConnector$ZKRebalancerListener.kafka$consumer$ZookeeperConsumerConnector$ZKRebalancerListener$$rebalance(ZookeeperConsumerConnector.scala:675) at kafka.consumer.ZookeeperConsumerConnector$ZKRebalancerListener$$anonfun$syncedRebalance$1$$anonfun$apply$mcV$sp$1.apply$mcVI$sp(ZookeeperConsumerConnector.scala:625) at scala.collection.immutable.Range.foreach$mVc$sp(Range.scala:142) at kafka.consumer.ZookeeperConsumerConnector$ZKRebalancerListener$$anonfun$syncedRebalance$1.apply$mcV$sp(ZookeeperConsumerConnector.scala:619) at kafka.consumer.ZookeeperConsumerConnector$ZKRebalancerListener$$anonfun$syncedRebalance$1.apply(ZookeeperConsumerConnector.scala:616) at kafka.consumer.ZookeeperConsumerConnector$ZKRebalancerListener$$anonfun$syncedRebalance$1.apply(ZookeeperConsumerConnector.scala:616) at kafka.metrics.KafkaTimer.time(KafkaTimer.scala:33) at kafka.consumer.ZookeeperConsumerConnector$ZKRebalancerListener.syncedRebalance(ZookeeperConsumerConnector.scala:615) at kafka.consumer.ZookeeperConsumerConnector$ZKRebalancerListener$$anon$1.run(ZookeeperConsumerConnector.scala:568) {code} -- This message was sent by Atlassian JIRA (v6.3.4#6332)