Stephan Birkl created AMQ-8629:
----------------------------------
Summary: MessageGroupHashBucket MBean returns data type not
deserializable by jmx/visualvm
Key: AMQ-8629
URL: https://issues.apache.org/jira/browse/AMQ-8629
Project: ActiveMQ
Issue Type: Bug
Components: Broker
Affects Versions: 5.16.5, 5.17.1, 5.18.0
Reporter: Stephan Birkl
Attachments: MessageGroupHashBucket.patch
We've switched our queues to MessageGroupHashBucket MessageGroupMap strategy.
One thing we've noticed is that when looking at the queues mbean in visualvm,
it now shows correctly "bucket" in the MessageGroupType attribute, but the
"MessageGroups" attribute is "unavailable" and when hovering the following
exception is shown:
java.rmi.UnmarshalException: ... ClassNotFoundException:
org.apache.activemq.memory.LRUMap
So basically visualvm cannot deserialize LRUMap, which of course makes sense.
MBeans should not return app specific classes.
To reproduce it, you can configure the following policy entry:
{noformat}
<policyEntry
queue=">">
<messageGroupMapFactory>
<messageGroupHashBucketFactory/>
</messageGroupMapFactory>
</policyEntry>{noformat}
I've checked the implementation of MessageGroupHashBucket.java and compared it
to the default implementation CachedMessageGroupMap.java.
CachedMessageGroupMap also maintains a LRUMap but converts it in method
getGroups() to a HashMap. getGroups() seems only to be used for the MBean as
far as I can see.
Therefore I wrote a small patch to basically take over the implementation from
CachedMessageGroupMap.java to MessageGroupHashBucket.java. Please find the
patch attached.
I've successfully compiled and tested it locally. The MBean attribute is now
correctly displayed and also from functionality point of view I did not see any
negative side effect.
Is there any chance to get this patch reviewed and added to 5.16.x, which we
currently use in production?
--
This message was sent by Atlassian Jira
(v8.20.7#820007)
