Thursday, January 29, 2009

POJOs can route too!

In Camel we have several really cool Domain Specific Languages (DSLs) for easily expressing routing rules. But you don't need to learn these to use Camel. Starting with a POJO, you can use annotations to produce, consume or route messages to any Camel endpoint.

Take the following bean for example

public class BeanThatTalksCamel {
@Produce(uri="activemq:myQueue")
ProducerTemplate producer;

@Consume(uri = "file:a/path")
public void onFileSendToQueue(String body) {
producer.sendBody(body);
}
}


We use the @Consume annotation to mark onFileSendToQueue as a consumer of any messages coming from the file:a/path endpoint. To enable the bean to send messages to the activemq:myQueue endpoint, we use the @Produce annotation. All conversions between Files, Strings and JMS Messages are automatic. Pretty easy huh?

We also have the @RecipientList annotation that turns any bean into a dynamic Recipient List.


public class RecipientListBean {
@Consume(uri = "activemq:myQueue")
@RecipientList
public List route(String body) {
// return list of recipients based on message body
}
}


Here we consume JMS messages from myQueue and based on the body, send it out to a list of recipients. Again, very easy. If you're a ServiceMix user, Gert mentions how to use this trick from a ServiceMix perspective too, go check it out!

If you need more info, I've put all of these concepts into a little demo here. As always, if you need help using Camel, please get in touch.

Monday, January 26, 2009

Helpful Maven Build Tips

Brian Fox recently posted some great tips to improve your Maven builds. You should check them out if you haven't already. I've been doing most of what he said already but one really caught my attention, and I will repost here:

#6 Print Test Failures to Standard Output

Tip: Enable -Dsurefire.useFile=false. This is a favorite of mine since this causes surefire to print test failures to standard out, where it will get included in the build failure log and email. This saves you from having to dig back onto the machine to find the surefire report just to see a simple stack trace. (to enable globally in settings.xml:true in an active profile)


I can't believe I didn't know about this option before. Having to grep through surefire log files has really annoyed me in the past... many kudos to Brian for sharing this!

Tuesday, January 20, 2009

Camel is now an Apache top level project!

As James and Claus have said today, Camel has been promoted to a top level project at Apache! This is a great vote of confidence for Camel, my fellow riders, and the rocking community. Thanks to all who've helped so far!

So, you should update your links to http://camel.apache.org now :)