Nirmal

Did some digging and the NPE is due to the fact that we are invoking a default 
constructor for whatever connection factory class is provided (i.e., 
‘org.exolab.jms.client.JmsConnectionFactory’). And that works for most major 
JMS providers, however for OpenJMS after looking at the code it is rather clear 
that the default constructor that is exposed was not exposed to be actually 
used by the developers but rather internal serialization use.

/**
     * Default constructor required for serialization
     */
    public JmsConnectionFactory() {
    }

Not sure why it was done this way . . ., but the NPE is due to the fact that 
the server proxy class is null so when it attempts to do 
Class.forName(proxyClassName) in getProxy() method it fails with NPE.

One other thing I noticed is that all OpenJMS examples are based on obtaining 
ConnectionFactory from JNDI for which we currently do not have support.

Once again, please raise the JIRA if you believe that it’s important to add 
such feature.

Cheers
Oleg
On Nov 1, 2016, at 9:29 AM, Oleg Zhurakousky 
<ozhurakou...@hortonworks.com<mailto:ozhurakou...@hortonworks.com>> wrote:

Nirmal

While ConsumeJMS was developed and tested with the idea of supporting multiple 
providers, ‘openjms’ was not the one that it was tested with.
I will look at the error and will follow up, but the fact that it already shows 
NPE means we have a bug somewhere, so please raise the JIRA 
(https://issues.apache.org/jira/browse/NIFI) if you don’t mind or let m know 
and I’ll do it.

Thank you for reporting it.
Cheers
Oleg


On Nov 1, 2016, at 8:35 AM, Nirmal Kumar 
<nirmal.ku...@impetus.co.in<mailto:nirmal.ku...@impetus.co.in>> wrote:

Hi All,

I am trying to read messages from openjms-0.7.7 using the ConsumeJMS Processor 
but getting following exception:

2016-11-01 14:43:17,260 ERROR [Timer-Driven Process Thread-4] 
o.apache.nifi.jms.processors.ConsumeJMS ConsumeJMS - 
JMSConsumer[destination:queue1; pub-sub:false;] ConsumeJMS - 
JMSConsumer[destination:queue1; pub-sub:false;] failed to process session due 
to org.springframework.jms.UncategorizedJmsException: Uncategorized exception 
occured during JMS processing; nested exception is javax.jms.JMSException: 
Failed to create proxy: java.lang.NullPointerException: 
org.springframework.jms.UncategorizedJmsException: Uncategorized exception 
occured during JMS processing; nested exception is javax.jms.JMSException: 
Failed to create proxy: java.lang.NullPointerException
2016-11-01 14:43:17,265 ERROR [Timer-Driven Process Thread-4] 
o.apache.nifi.jms.processors.ConsumeJMS
org.springframework.jms.UncategorizedJmsException: Uncategorized exception 
occured during JMS processing; nested exception is javax.jms.JMSException: 
Failed to create proxy: java.lang.NullPointerException
        at 
org.springframework.jms.support.JmsUtils.convertJmsAccessException(JmsUtils.java:316)
 ~[na:na]
        at 
org.springframework.jms.support.JmsAccessor.convertJmsAccessException(JmsAccessor.java:169)
 ~[na:na]
        at 
org.springframework.jms.core.JmsTemplate.execute(JmsTemplate.java:497) ~[na:na]
        at 
org.springframework.jms.core.JmsTemplate.receiveSelected(JmsTemplate.java:764) 
~[na:na]
        at 
org.springframework.jms.core.JmsTemplate.receive(JmsTemplate.java:738) ~[na:na]
        at 
org.springframework.jms.core.JmsTemplate.receive(JmsTemplate.java:727) ~[na:na]
        at 
org.apache.nifi.jms.processors.JMSConsumer.consume(JMSConsumer.java:65) ~[na:na]
        at 
org.apache.nifi.jms.processors.ConsumeJMS.rendezvousWithJms(ConsumeJMS.java:79) 
~[na:na]
        at 
org.apache.nifi.jms.processors.AbstractJMSProcessor.onTrigger(AbstractJMSProcessor.java:136)
 ~[na:na]
        at 
org.apache.nifi.jms.processors.ConsumeJMS.onTrigger(ConsumeJMS.java:50) ~[na:na]
        at 
org.apache.nifi.processor.AbstractProcessor.onTrigger(AbstractProcessor.java:27)
 ~[nifi-api-1.0.0.jar:1.0.0]
        at 
org.apache.nifi.controller.StandardProcessorNode.onTrigger(StandardProcessorNode.java:1064)
 ~[nifi-framework-core-1.0.0.jar:1.0.0]
        at 
org.apache.nifi.controller.tasks.ContinuallyRunProcessorTask.call(ContinuallyRunProcessorTask.java:136)
 [nifi-framework-core-1.0.0.jar:1.0.0]
        at 
org.apache.nifi.controller.tasks.ContinuallyRunProcessorTask.call(ContinuallyRunProcessorTask.java:47)
 [nifi-framework-core-1.0.0.jar:1.0.0]
        at 
org.apache.nifi.controller.scheduling.TimerDrivenSchedulingAgent$1.run(TimerDrivenSchedulingAgent.java:132)
 [nifi-framework-core-1.0.0.jar:1.0.0]
        at 
java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511) 
[na:1.8.0_45]
        at java.util.concurrent.FutureTask.runAndReset(FutureTask.java:308) 
[na:1.8.0_45]
        at 
java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$301(ScheduledThreadPoolExecutor.java:180)
 [na:1.8.0_45]
        at 
java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:294)
 [na:1.8.0_45]
        at 
java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) 
[na:1.8.0_45]
        at 
java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) 
[na:1.8.0_45]
        at java.lang.Thread.run(Thread.java:745) [na:1.8.0_45]
Caused by: javax.jms.JMSException: Failed to create proxy: 
java.lang.NullPointerException
        at 
org.exolab.jms.client.JmsConnectionFactory.getProxy(JmsConnectionFactory.java:169)
 ~[na:na]
        at org.exolab.jms.client.JmsConnection.<init>(JmsConnection.java:174) 
~[na:na]
        at 
org.exolab.jms.client.JmsConnectionFactory.createConnection(JmsConnectionFactory.java:284)
 ~[na:na]
        at 
org.exolab.jms.client.JmsConnectionFactory.createConnection(JmsConnectionFactory.java:266)
 ~[na:na]
        at 
org.springframework.jms.connection.UserCredentialsConnectionFactoryAdapter.doCreateConnection(UserCredentialsConnectionFactoryAdapter.java:181)
 ~[na:na]
        at 
org.springframework.jms.connection.UserCredentialsConnectionFactoryAdapter.createConnection(UserCredentialsConnectionFactoryAdapter.java:152)
 ~[na:na]
        at 
org.springframework.jms.connection.SingleConnectionFactory.doCreateConnection(SingleConnectionFactory.java:365)
 ~[na:na]
        at 
org.springframework.jms.connection.SingleConnectionFactory.initConnection(SingleConnectionFactory.java:305)
 ~[na:na]
        at 
org.springframework.jms.connection.SingleConnectionFactory.getConnection(SingleConnectionFactory.java:283)
 ~[na:na]
        at 
org.springframework.jms.connection.SingleConnectionFactory.createConnection(SingleConnectionFactory.java:224)
 ~[na:na]
        at 
org.springframework.jms.support.JmsAccessor.createConnection(JmsAccessor.java:180)
 ~[na:na]
        at 
org.springframework.jms.core.JmsTemplate.execute(JmsTemplate.java:484) ~[na:na]
        ... 19 common frames omitted


I have configured the JMSConnectionFactoryProvider with the following 
properties:

MQ ConnectionFactory Implementation

org.exolab.jms.client.JmsConnectionFactory

Actual

MQ Client Libraries path (i.e., /usr/jms/lib)

/user/nirmal/OpenJMS/openjms-0.7.7/lib

The lib directory for OpenJMS



I also tried org.exolab.jms.client.JmsXAConnectionFactory in the above #1 
property but again the same exception logs.

Not sure if somebody tested the ConsumeJMS / PublishJMS processors with OpenJMS?

Thanks,
-Nirmal


________________________________






NOTE: This message may contain information that is confidential, proprietary, 
privileged or otherwise protected by law. The message is intended solely for 
the named addressee. If received in error, please destroy and notify the 
sender. Any use of this email is prohibited when received in error. Impetus 
does not represent, warrant and/or guarantee, that the integrity of this 
communication has been maintained nor that the communication is free of errors, 
virus, interception or interference.


Reply via email to