Hi Kafka people, I'm joining a bunch of Kafka Topics using Kafka Streams, with the Kafka 0.10.1 release candidate.
It runs ok for a few thousand of messages, and then it dies with the following exception: Exception in thread "StreamThread-1" java.lang.NullPointerException at org.apache.kafka.streams.state.internals.NamedCache.evict(NamedCache.java:194) at org.apache.kafka.streams.state.internals.ThreadCache.maybeEvict(ThreadCache.java:190) at org.apache.kafka.streams.state.internals.ThreadCache.put(ThreadCache.java:121) at org.apache.kafka.streams.state.internals.CachingKeyValueStore.get(CachingKeyValueStore.java:147) at org.apache.kafka.streams.state.internals.CachingKeyValueStore.get(CachingKeyValueStore.java:134) at org.apache.kafka.streams.kstream.internals.KTableReduce$KTableAggregateValueGetter.get(KTableReduce.java:121) at org.apache.kafka.streams.kstream.internals.KTableKTableLeftJoin$KTableKTableLeftJoinProcessor.process(KTableKTableLeftJoin.java:77) at org.apache.kafka.streams.kstream.internals.KTableKTableLeftJoin$KTableKTableLeftJoinProcessor.process(KTableKTableLeftJoin.java:48) at org.apache.kafka.streams.processor.internals.ProcessorNode.process(ProcessorNode.java:82) at org.apache.kafka.streams.processor.internals.ProcessorContextImpl.forward(ProcessorContextImpl.java:204) at org.apache.kafka.streams.kstream.internals.KTableFilter$KTableFilterProcessor.process(KTableFilter.java:83) at org.apache.kafka.streams.kstream.internals.KTableFilter$KTableFilterProcessor.process(KTableFilter.java:73) at org.apache.kafka.streams.processor.internals.ProcessorNode.process(ProcessorNode.java:82) at org.apache.kafka.streams.processor.internals.ProcessorContextImpl.forward(ProcessorContextImpl.java:204) at org.apache.kafka.streams.kstream.internals.KTableFilter$KTableFilterProcessor.process(KTableFilter.java:83) at org.apache.kafka.streams.kstream.internals.KTableFilter$KTableFilterProcessor.process(KTableFilter.java:73) at org.apache.kafka.streams.processor.internals.ProcessorNode.process(ProcessorNode.java:82) at org.apache.kafka.streams.processor.internals.ProcessorContextImpl.forward(ProcessorContextImpl.java:204) at org.apache.kafka.streams.kstream.internals.KTableKTableJoinMerger$KTableKTableJoinMergeProcessor.process(KTableKTableJoinMerger.java:52) at org.apache.kafka.streams.kstream.internals.KTableKTableJoinMerger$KTableKTableJoinMergeProcessor.process(KTableKTableJoinMerger.java:49) at org.apache.kafka.streams.processor.internals.ProcessorNode.process(ProcessorNode.java:82) at org.apache.kafka.streams.processor.internals.ProcessorContextImpl.forward(ProcessorContextImpl.java:204) at org.apache.kafka.streams.kstream.internals.KTableKTableRightJoin$KTableKTableRightJoinProcessor.process(KTableKTableRightJoin.java:83) at org.apache.kafka.streams.kstream.internals.KTableKTableRightJoin$KTableKTableRightJoinProcessor.process(KTableKTableRightJoin.java:49) at org.apache.kafka.streams.processor.internals.ProcessorNode.process(ProcessorNode.java:82) at org.apache.kafka.streams.processor.internals.ProcessorContextImpl.forward(ProcessorContextImpl.java:204) at org.apache.kafka.streams.kstream.internals.ForwardingCacheFlushListener.apply(ForwardingCacheFlushListener.java:35) at org.apache.kafka.streams.state.internals.CachingKeyValueStore.maybeForward(CachingKeyValueStore.java:97) at org.apache.kafka.streams.state.internals.CachingKeyValueStore.access$000(CachingKeyValueStore.java:34) at org.apache.kafka.streams.state.internals.CachingKeyValueStore$1.apply(CachingKeyValueStore.java:84) at org.apache.kafka.streams.state.internals.NamedCache.flush(NamedCache.java:117) at org.apache.kafka.streams.state.internals.NamedCache.evict(NamedCache.java:196) at org.apache.kafka.streams.state.internals.ThreadCache.maybeEvict(ThreadCache.java:190) at org.apache.kafka.streams.state.internals.ThreadCache.put(ThreadCache.java:121) at org.apache.kafka.streams.state.internals.CachingKeyValueStore.put(CachingKeyValueStore.java:187) at org.apache.kafka.streams.state.internals.CachingKeyValueStore.put(CachingKeyValueStore.java:182) at org.apache.kafka.streams.kstream.internals.KTableReduce$KTableReduceProcessor.process(KTableReduce.java:92) at org.apache.kafka.streams.kstream.internals.KTableReduce$KTableReduceProcessor.process(KTableReduce.java:52) at org.apache.kafka.streams.processor.internals.ProcessorNode.process(ProcessorNode.java:82) at org.apache.kafka.streams.processor.internals.ProcessorContextImpl.forward(ProcessorContextImpl.java:204) at org.apache.kafka.streams.processor.internals.SourceNode.process(SourceNode.java:66) at org.apache.kafka.streams.processor.internals.StreamTask.process(StreamTask.java:177) at org.apache.kafka.streams.processor.internals.StreamThread.runLoop(StreamThread.java:427) at org.apache.kafka.streams.processor.internals.StreamThread.run(StreamThread.java:235) I know this isn't a great bug report, as I can't seem to reproduce this in a more sandboxed situation. Any tips / ideas for further steps?
