ConcurrentModificationException when calling SimpMessagingTemplate.convertAndSend [SPR-13185]

[spring-projects-issues]

Henrik Olsson opened SPR-13185 and commented

18:35:42.312 [http-nio-8080-exec-47] ERROR o.s.w.s.m.StompSubProtocolHandler - Error publishing SessionSubscribeEvent[GenericMessage [payload=byte[0], headers={simpMessageType=SUBSCRIBE, stompCommand=SUBSCRIBE, nativeHeaders={id=[/api/event-lists/list], destination=[/api/event-lists/list]}, simpSessionAttributes={scopedTarget.scopedRequestsPerSessionCounter=session.ScopedRequestsPerSessionCounter@48538a7d, org.springframework.messaging.simp.SimpAttributes.DESTRUCTION_CALLBACK.scopedTarget.scopedRequestsPerSessionCounter=org.springframework.beans.factory.support.DisposableBeanAdapter@46758ba2}, simpSubscriptionId=/api/event-lists/list, simpSessionId=ialw0jal, simpDestination=/api/event-lists/list}]].
org.springframework.messaging.MessageDeliveryException: Failed to handle GenericMessage [payload=byte[3067], headers={simpMessageType=MESSAGE, stompCommand=SEND, nativeHeaders={id=[/api/event-lists/list], destination=[/api/event-lists/list], type=[FULL], simpOrigDestination=[/user/request-response]}, simpSessionAttributes={scopedTarget.scopedRequestsPerSessionCounter=session.ScopedRequestsPerSessionCounter@48538a7d, org.springframework.messaging.simp.SimpAttributes.DESTRUCTION_CALLBACK.scopedTarget.scopedRequestsPerSessionCounter=org.springframework.beans.factory.support.DisposableBeanAdapter@46758ba2}, simpSubscriptionId=/api/event-lists/list, contentType=application/json;charset=UTF-8, simpSessionId=ialw0jal, simpDestination=/request-response-userialw0jal}] to org.springframework.messaging.support.ExecutorSubscribableChannel$SendTask@fe59cf8 in SimpleBroker[DefaultSubscriptionRegistry[cache[509 destination(s)], registry[584 sessions]]]; nested exception is java.util.ConcurrentModificationException
        at org.springframework.messaging.support.ExecutorSubscribableChannel$SendTask.run(ExecutorSubscribableChannel.java:144) ~[spring-messaging-4.1.6.RELEASE.jar:4.1.6.RELEASE]
        at org.springframework.messaging.support.ExecutorSubscribableChannel.sendInternal(ExecutorSubscribableChannel.java:91) ~[spring-messaging-4.1.6.RELEASE.jar:4.1.6.RELEASE]
        at org.springframework.messaging.support.AbstractMessageChannel.send(AbstractMessageChannel.java:117) ~[spring-messaging-4.1.6.RELEASE.jar:4.1.6.RELEASE]
        at org.springframework.messaging.support.AbstractMessageChannel.send(AbstractMessageChannel.java:104) ~[spring-messaging-4.1.6.RELEASE.jar:4.1.6.RELEASE]
        at org.springframework.messaging.simp.SimpMessagingTemplate.sendInternal(SimpMessagingTemplate.java:184) ~[spring-messaging-4.1.6.RELEASE.jar:4.1.6.RELEASE]
        at org.springframework.messaging.simp.SimpMessagingTemplate.doSend(SimpMessagingTemplate.java:176) ~[spring-messaging-4.1.6.RELEASE.jar:4.1.6.RELEASE]
        at org.springframework.messaging.simp.SimpMessagingTemplate.doSend(SimpMessagingTemplate.java:47) ~[spring-messaging-4.1.6.RELEASE.jar:4.1.6.RELEASE]
        at org.springframework.messaging.core.AbstractMessageSendingTemplate.send(AbstractMessageSendingTemplate.java:95) ~[spring-messaging-4.1.6.RELEASE.jar:4.1.6.RELEASE]
        at org.springframework.messaging.simp.user.UserDestinationMessageHandler.handleMessage(UserDestinationMessageHandler.java:190) ~[spring-messaging-4.1.6.RELEASE.jar:4.1.6.RELEASE]
        at org.springframework.messaging.support.ExecutorSubscribableChannel$SendTask.run(ExecutorSubscribableChannel.java:135) ~[spring-messaging-4.1.6.RELEASE.jar:4.1.6.RELEASE]
        at org.springframework.messaging.support.ExecutorSubscribableChannel.sendInternal(ExecutorSubscribableChannel.java:91) ~[spring-messaging-4.1.6.RELEASE.jar:4.1.6.RELEASE]
        at org.springframework.messaging.support.AbstractMessageChannel.send(AbstractMessageChannel.java:117) ~[spring-messaging-4.1.6.RELEASE.jar:4.1.6.RELEASE]
        at org.springframework.messaging.support.AbstractMessageChannel.send(AbstractMessageChannel.java:104) ~[spring-messaging-4.1.6.RELEASE.jar:4.1.6.RELEASE]
        at org.springframework.messaging.simp.SimpMessagingTemplate.sendInternal(SimpMessagingTemplate.java:184) ~[spring-messaging-4.1.6.RELEASE.jar:4.1.6.RELEASE]
        at org.springframework.messaging.simp.SimpMessagingTemplate.doSend(SimpMessagingTemplate.java:176) ~[spring-messaging-4.1.6.RELEASE.jar:4.1.6.RELEASE]
        at org.springframework.messaging.simp.SimpMessagingTemplate.doSend(SimpMessagingTemplate.java:47) ~[spring-messaging-4.1.6.RELEASE.jar:4.1.6.RELEASE]
        at org.springframework.messaging.core.AbstractMessageSendingTemplate.send(AbstractMessageSendingTemplate.java:95) ~[spring-messaging-4.1.6.RELEASE.jar:4.1.6.RELEASE]
        at org.springframework.messaging.core.AbstractMessageSendingTemplate.convertAndSend(AbstractMessageSendingTemplate.java:133) ~[spring-messaging-4.1.6.RELEASE.jar:4.1.6.RELEASE]
        at org.springframework.messaging.simp.SimpMessagingTemplate.convertAndSendToUser(SimpMessagingTemplate.java:224) ~[spring-messaging-4.1.6.RELEASE.jar:4.1.6.RELEASE]
        at org.springframework.messaging.simp.SimpMessagingTemplate.convertAndSendToUser(SimpMessagingTemplate.java:208) ~[spring-messaging-4.1.6.RELEASE.jar:4.1.6.RELEASE]
   [  .... application frames ..... ] 
Caused by: java.util.ConcurrentModificationException: null
        at java.util.LinkedList$ListItr.checkForComodification(LinkedList.java:966) ~[na:1.8.0_45]
        at java.util.LinkedList$ListItr.next(LinkedList.java:888) ~[na:1.8.0_45]
        at org.springframework.messaging.simp.broker.SimpleBrokerMessageHandler.sendMessageToSubscribers(SimpleBrokerMessageHandler.java:201) ~[spring-messaging-4.1.6.RELEASE.jar:4.1.6.RELEASE]
        at org.springframework.messaging.simp.broker.SimpleBrokerMessageHandler.handleMessageInternal(SimpleBrokerMessageHandler.java:149) ~[spring-messaging-4.1.6.RELEASE.jar:4.1.6.RELEASE]
        at org.springframework.messaging.simp.broker.AbstractBrokerMessageHandler.handleMessage(AbstractBrokerMessageHandler.java:238) ~[spring-messaging-4.1.6.RELEASE.jar:4.1.6.RELEASE]
        at org.springframework.messaging.support.ExecutorSubscribableChannel$SendTask.run(ExecutorSubscribableChannel.java:135) ~[spring-messaging-4.1.6.RELEASE.jar:4.1.6.RELEASE]
        ... 73 common frames omitted

---

Affects: 4.1.6

Issue Links:

• ConcurrentModificationException in SimpleBrokerMessageHandler [SPR-12665] #17264 ConcurrentModificationException in SimpleBrokerMessageHandler
• Support 'selector' header for subscriptions with SimpleBrokerMessageHandler [SPR-12884] #17482 Support 'selector' header for subscriptions with SimpleBrokerMessageHandler
• LinkedMultiValueMap should allow for deep copy of List values [SPR-13201] #17793 LinkedMultiValueMap should allow for deep copy of List values
• NullPointerException in DefaultSubscriptionRegistry.removeSubscription [SPR-13205] #17797 NullPointerException in DefaultSubscriptionRegistry.removeSubscription
• UriComponentsBuilder.uriComponents doesn't properly clone unmodifiable queryParams [SPR-17256] #21789 UriComponentsBuilder.uriComponents doesn't properly clone unmodifiable queryParams

Referenced from: commits ca9beea, 16cbfcf, f0175bc

[spring-projects-issues]

Juergen Hoeller commented

It looks like this should have been fixed with #17264 as of 4.1.5 already...

Juergen

[spring-projects-issues]

Rossen Stoyanchev commented

Yes the fix for SPR-12665 was meant to ensure that the MultiValueMap instances in the accessCache never change. However it looks like the copy constructor of LinkedMultiValueMap does not do a deep copy of the List for each value. This is a surprise since LinkedMultiValueMap is aware of the List values and there is an argument to be made for fixing it there. Either way we need to ensure the MultiValueMap in the accessCache is independent of that in the updateCache.

[spring-projects-issues]

Juergen Hoeller commented

Indeed, it looks like @LinkedMultiValueMap should really be doing a deep copy of its List values there.

Juergen

[spring-projects-issues]

Rossen Stoyanchev commented

I've added a test that demonstrates this issue does not affect 4.2. The same test fails in 4.1.x with a ConcurrentModificationException. The reason for the difference is the following commit b6327a that expanded subscription support for 4.2 (adding a 'selector' expression-based header) and in the process changed subscriptions from being stored in HashSet to CopyOnWriteArraySet.

[spring-projects-issues]

Rossen Stoyanchev commented

Never mind my last comment. I added the wrong test. The issue affects 4.2 just the same.

[spring-projects-issues]

Juergen Hoeller commented

Fixed in 4.2 through using LinkedMultiValueMap's new deepCopy() mechanism.

4.1.8 backport following based on local deep copies within DefaultSubscriptionRegistry, plus the CopyOnWriteArraySet part from #17482.

Juergen