Help with integration of custom beans xml format

[CameronBraid]

I am trying to help the ActiveMQ people with integration of their configuration file format into a spring application context.

Currently they use a custom XmlBeanDefinitionReader that uses XSLT to transform their xml file format into a normal spring format.

This works fine when someone loads their configuration by instantiating a ActiveMQBeanFactory instance (which uses ActiveMQBeanDefinitionReader internally)

The issue that I am facing is the integration of this process with a normal applicationContext.xml file.

I want to merge the bean definitions from a transfomed ativeMQ.xml file into an existing application context. How can this be done ?

I attempted to do it with :


<bean id="activeMQ" class="ActiveMQ">
<property name="location"><value>classpath:activeMQ.xml</value></property>
</bean>

class ActiveMQ implements InitializingBean, ApplicationContextAware {
...
public void afterPropertiesSet() throws Exception {

// validation of properties here

BeanDefinitionRegistry registry = null;

if (parentContext instanceof ConfigurableApplicationContext) {
// merge the bean befinitions into the parent's registry
BeanFactory beanFactory = ((ConfigurableApplicationContext)parentContext).ge tBeanFactory();
if (beanFactory instanceof BeanDefinitionRegistry) {
registry = (BeanDefinitionRegistry)beanFactory;
new ActiveMQBeanDefinitionReader(registry).loadBeanDef initions(location);
}
}

// handle (registry == null) case

}

}


This code causes an exception

java.util.ConcurrentModificationException
at java.util.LinkedList$ListItr.checkForComodificatio n(LinkedList.java:552)
at java.util.LinkedList$ListItr.next(LinkedList.java: 488)
at org.springframework.beans.factory.support.DefaultL istableBeanFactory.preInstantiateSingletons(Defaul tListableBeanFactory.java:198)
at org.springframework.context.support.AbstractApplic ationContext.refresh(AbstractApplicationContext.ja va:279)
at org.springframework.context.support.ClassPathXmlAp plicationContext.<init>(ClassPathXmlApplicationContext.java:81)
at org.springframework.context.support.ClassPathXmlAp plicationContext.<init>(ClassPathXmlApplicationContext.java:66)
at org.springframework.context.support.ClassPathXmlAp plicationContext.<init>(ClassPathXmlApplicationContext.java:57)
at Main.main(Main.java:13)


I have also considered making a child context, and load the activeMQ definitions into there, but the problem is that some beans defined in activeMQ.xml may be needed in the parent context.

Any thoughts / ideas / suggestions ?

[jstrachan]

After a bit of chat on the ActiveMQ irc (irc://irc.codehaus.org/activemq) we've figured this one out.

The ActiveConnectionFactory is gonna have a property of the broker, then we'll use a BrokerFactoryBean which can take a Spring Resource as a constructor / property to allow Spring to configure the broker on a connection factory - yet keeping the broker XML config file separate to the normal Spring XML configuration.

This allows us to use a custom XMLBeanFactory for the ActiveMQ broker - such as to take advantage of our customized ActiveMQ config file format (to save typing, using elements like broker, connection, transport etc).

So I think we've got this one sorted now