Question

我正在使用带有KaQdb持久消息传递的AMQ 5.6的AMQ消息组，并定期在日志中看到此WARN。我没有看到由此引起的任何具体错误，但我想知道这是什么副作用等等。

我的消费者是一个Camel（2.9.2）路由，maxConcurrentConsumers = 5（使用AMQ连接池等）。我会尝试在某个时候将其归结为单元测试......现在，这是堆栈跟踪

Async error occurred: java.util.concurrent.ExecutionException: java.util.ConcurrentModificationException
java.util.concurrent.ExecutionException: java.util.ConcurrentModificationException
    at java.util.concurrent.FutureTask$Sync.innerGet(FutureTask.java:222)
    at java.util.concurrent.FutureTask.get(FutureTask.java:83)
    at org.apache.activemq.broker.region.Queue.doMessageSend(Queue.java:785)
    at org.apache.activemq.broker.region.Queue.send(Queue.java:707)
    at org.apache.activemq.broker.region.AbstractRegion.send(AbstractRegion.java:407)
    at org.apache.activemq.broker.region.RegionBroker.send(RegionBroker.java:503)
    at org.apache.activemq.broker.jmx.ManagedRegionBroker.send(ManagedRegionBroker.java:305)
    at org.apache.activemq.broker.BrokerFilter.send(BrokerFilter.java:129)
    at org.apache.activemq.broker.CompositeDestinationBroker.send(CompositeDestinationBroker.java:96)
    at org.apache.activemq.broker.TransactionBroker.send(TransactionBroker.java:306)
    at org.apache.activemq.broker.MutableBrokerFilter.send(MutableBrokerFilter.java:135)
    at org.apache.activemq.broker.TransportConnection.processMessage(TransportConnection.java:453)
    at org.apache.activemq.command.ActiveMQMessage.visit(ActiveMQMessage.java:681)
    at org.apache.activemq.broker.TransportConnection.service(TransportConnection.java:292)
    at org.apache.activemq.broker.TransportConnection$1.onCommand(TransportConnection.java:150)
    at org.apache.activemq.transport.ResponseCorrelator.onCommand(ResponseCorrelator.java:116)
    at org.apache.activemq.transport.MutexTransport.onCommand(MutexTransport.java:50)
    at org.apache.activemq.transport.vm.VMTransport.iterate(VMTransport.java:231)
    at org.apache.activemq.thread.PooledTaskRunner.runTask(PooledTaskRunner.java:122)
    at org.apache.activemq.thread.PooledTaskRunner$1.run(PooledTaskRunner.java:43)
    at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
    at java.lang.Thread.run(Thread.java:680)
Caused by: java.util.ConcurrentModificationException
    at java.util.HashMap$HashIterator.nextEntry(HashMap.java:793)
    at java.util.HashMap$KeyIterator.next(HashMap.java:828)
    at org.apache.activemq.util.MarshallingSupport.marshalPrimitiveMap(MarshallingSupport.java:64)
    at org.apache.activemq.command.Message.beforeMarshall(Message.java:210)
    at org.apache.activemq.command.ActiveMQObjectMessage.beforeMarshall(ActiveMQObjectMessage.java:199)
    at org.apache.activemq.openwire.v6.MessageMarshaller.looseMarshal(MessageMarshaller.java:277)
    at org.apache.activemq.openwire.v6.ActiveMQMessageMarshaller.looseMarshal(ActiveMQMessageMarshaller.java:111)
    at org.apache.activemq.openwire.v6.ActiveMQObjectMessageMarshaller.looseMarshal(ActiveMQObjectMessageMarshaller.java:111)
    at org.apache.activemq.openwire.OpenWireFormat.marshal(OpenWireFormat.java:168)
    at org.apache.activemq.store.kahadb.KahaDBStore$KahaDBMessageStore.addMessage(KahaDBStore.java:429)
    at org.apache.activemq.store.kahadb.KahaDBStore$StoreQueueTask.run(KahaDBStore.java:1177)

Answer 1

为此记录了一个JIRA（AMQ-4092），这听起来像是KahaDB和消息组合的问题。设置concurrentStoreAndDispatchQueues = false解决了这个问题（感谢Gary Tully提出的建议）

ActiveMQ消息组 - ConcurrentModificationException

1 个答案: