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Improvement
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    Resolution: Unresolved
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Major
 
If you accidentally store something nonserializable in a local variable, you get a nasty stack trace mentioning org.jboss.marshalling.river.RiverMarshaller.doWriteObject and other things which will make no sense to a user and imply a bug in Workflow rather than in your script.
RiverWriter should defend better against this. It could replace the bad object with null, after printing a warning in the log. Or it could simply replace it with a pickle that rehydrates to null or throws an exception if you ever resume this flow after a restart. I think replacement with null is preferable since in most cases you did not really need the object to be saved and the flow could have continued without it.
- is related to
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JENKINS-27458 Serialization error at end of flow not reported properly in build log, only Jenkins log
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 - Resolved
 
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JENKINS-27421 Unserializable iterator & entry classes from Java Collections
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 - Resolved
 
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JENKINS-26137 Mysterious serialization errors
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 - Closed
 
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JENKINS-32213 Must declare classes to implement Serializable
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 - Resolved
 
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