I am trying to consume messages from a topic on UM using the following JAVA Nirvana jar libraries,

nClient.jar
nJ2EE.jar
nJMS.jar
nP2P.jar

However we receive the following error which appear to originate from the Nirvana code. On doing a tcpdump on the UM server endpoint we see the contents of the JMS message from the topic being sent when consumed by our client code. However our client code fails at the point of receiving the message with the following stacktrace.

[color=red]javax.jms.JMSException: Error while receiving message - java.lang.NullPointerException
at com.pcbsys.nirvana.nJMS.MessageConsumerImpl.receive(MessageConsumerImpl.java:1697)

Caused by: java.lang.NullPointerException
at com.pcbsys.nirvana.nJMS.MessageConsumerImpl.convertEvent(MessageConsumerImpl.java:2083)
at com.pcbsys.nirvana.nJMS.MessageConsumerImpl.processTopicAcknowledgement(MessageConsumerImpl.java:1601)
at com.pcbsys.nirvana.nJMS.MessageConsumerImpl.receiveTopicEvent(MessageConsumerImpl.java:1663)
at com.pcbsys.nirvana.nJMS.MessageConsumerImpl.receive(MessageConsumerImpl.java:1686)
… 83 more[/color]

Our connection parameters are the following
clientGroup = “client-group:group”
providerUrl = “nsp://xxx.xxx.xxxx.xxx:nnnnn”
factoryLookupName = “JMS_CF”
initialContextFactory = “com.pcbsys.nirvana.nSpace.NirvanaContextFactory”

Can anyone tell me what is causing this exception?

Solved - we cleared down the topic and deleted and re-created the clientGroup on the UM Server.

This appeared to work fine.