englishteeth.co.uk

After I sort of set a challenge when thinking about Convention over Configuration, I had to see if it was in fact doable in a framework that exploits the principals.

This was straight from the grails site for the JMS Plugin, but in less than 30 minutes I have an exposed message driven bean receiving a JMS message and that includes downloading the plug-in and Apache ActiveMQ.

As I say, I had to go to download the plugin since, due to what I think is a proxy issue, I couldn’t directly use grails install-plugin jms

Though the following worked fine enough
grails install-plugin C:\Local\downloads\grails-jms-0.3.zip

I needed to copy over three libraries from the ActiveMQ distribution and add a little bit of Spring

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE beans PUBLIC "-//SPRING//DTD BEAN//EN" "http://www.springframework.org/dtd/spring-beans.dtd">
<beans>
    <bean id = "connectionFactory" class = "org.apache.activemq.ActiveMQConnectionFactory">
        <property name = "brokerURL" value = "tcp://localhost:61616"/>
    </bean>
</beans>

I then added the service (much like the xfire one) to receive messages (the message driven bean).

class SampleQueueService {
    static expose = ['jms']

    def onMessage(messageObject) {
       println "GOT MESSAGE: $messageObject"
    }

}

Then it was just a matter of running the grails console and entering three lines to send a messge:

def connectionFactory = ctx.getBean("connectionFactory")
def template = new org.springframework.jms.core.JmsTemplate(connectionFactory)
template.convertAndSend("sampleQueue", "Message Posted!")

et voilà
GOT MESSAGE: Message Posted!
I may be easily pleased, but I found that quite satisfying.