i used kafka as event bus. but now i’m removing it.
in one application, i only use simple event bus and command handler, event handler
but it suddenly occured the error.
2022-06-21 07:05:51.226 INFO 1 --- [untProcessor]-0] o.a.e.TrackingEventProcessor : An error occurred while attempting to claim a token for segment: 0. Will retry later...
java.lang.ClassCastException: org.axonframework.serialization.UnknownSerializedType cannot be cast to org.axonframework.eventhandling.TrackingToken
at org.axonframework.eventhandling.tokenstore.AbstractTokenEntry.getToken(AbstractTokenEntry.java:121) ~[axon-messaging-4.5.8.jar:4.5.8]
at org.axonframework.extensions.mongo.eventsourcing.tokenstore.MongoTokenStore.fetchToken(MongoTokenStore.java:179) ~[axon-mongo-4.5.jar:4.5]
at org.axonframework.eventhandling.TrackingEventProcessor$WorkerLauncher.lambda$run$2(TrackingEventProcessor.java:1096) ~[axon-messaging-4.5.8.jar:4.5.8]
what’s wrong with it? if i remove mongo and re-install, it work well.
but first using kafka as event bus, and then change it to simple event bus, it didn’t work well.
i don’t know why it happen
please someone tell me the reason
how it work?