Re: [Springframework-developer] message driven POJOs, a lightweight JCA container available

[<jas...@ma...>]

On 28 Oct 2004, at 09:52, j=FCrgen h=F6ller [werk3AT] wrote:
> If there's an actual need to pool those target listeners, this could =20=

> always be achieved through a ProxyFactoryBean with a pooling =20
> TargetSource, with the proxy implementing the MessageListener =20
> interface: =46rom the point of view of the ActiveMQ message =
dispatcher, =20
> it would simply keep calling the shared MessageListener onMessage =20
> method, but this time on the proxy which will delegate to one of the =20=

> instances in its backend pool.

I went a head and refactored to just use a MessageListener and so then =20=

its up to the MessageListener instance to handle pooling - if its =20
needed. This makes the code much cleaner - great suggestion j=FCrgen.


I tried using the ProxyFactoryBean. Firstly this introduced a new =20
runtime dependency on cglib. Secondly it created this exception..

org.springframework.beans.factory.BeanCreationException: Error creating =20=

bean with name 'inboundMessageB' defined in class path resource =20
[spring-with-proxyfactory.xml]: Can't resolve reference to bean =20
'pooledEchoBean' while setting property 'messageListener'; nested =20
exception is org.springframework.beans.factory.BeanCreationException: =20=

Error creating bean with name 'pooledEchoBean' defined in class path =20
resource [spring-with-proxyfactory.xml]: Initialization of bean failed; =20=

nested exception is org.aopalliance.aop.AspectException: null
org.springframework.beans.factory.BeanCreationException: Error creating =20=

bean with name 'pooledEchoBean' defined in class path resource =20
[spring-with-proxyfactory.xml]: Initialization of bean failed; nested =20=

exception is org.aopalliance.aop.AspectException: null
java.lang.IllegalStateException: Unknown callback class =20
org.springframework.aop.framework.Cglib2AopProxy$DynamicAdvisedIntercept=20=

or
	at =20
net.sf.cglib.proxy.CallbackUtils.getGenerator(CallbackUtils.java:102)

The XML config file I was using is here...

http://cvs.activemq.codehaus.org/viewrep/activemq/activemq/modules/=20
container/src/test/org/codehaus/activemq/jca/spring-with-=20
proxyfactory.xml?r=3D1.1

and the test case is JCAContainerWithProxyFactoryTest.

Any ideas why I get this error? Its OK to use a ProxyFactoryBean with a =20=

pooled TargetSource without using any AOP advice right?


As a work around and to avoid the cglib dependency, I've added a little =20=

TargetSourceMessageListener helper class which works in a similar =20
way...

http://cvs.activemq.codehaus.org/viewrep/activemq/activemq/modules/=20
container/src/test/org/codehaus/activemq/jca/spring.xml?r=3D1.3
In terms of simplicity in the XML configuration file they're of similar =20=

order.


Incidentally there's also an XA based test case to show how to use XA =20=

based message consumption; you basically just ocnfigure the =20
TransactionManager to use.

http://cvs.activemq.codehaus.org/viewrep/activemq/activemq/modules/=20
container/src/test/org/codehaus/activemq/jca/spring-with-xa.xml?r=3D1.1

In this particular test case,  JCAContainerUsingXATest  we just use =20
JOTM directly.

James
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