About Jboss

[Pradeep bhatt]

JBoss is a microkernel based server. What does it mean?

[Lasse Koskela]

Well, I am not a Latest Buzzword Certified Professional, but I think the JBoss micro kernel is just a kind of component registry where services are registered and from where one service looks up another.

[Pradeep bhatt]

Thanks Lasse!
What does it mean - "To create service in JBOSS"? I am talking about SAR files.

[norman richards]

In JBoss terms, the services are the components that the application server provides that your application can take care of. Your transaction manager, database connection pools, JMS server, etc... are all examples of services. Really, EVERYTHING in JBoss is a service.
Getting back to the microkernel idea, what is interesting about the JBoss architecture is that the core of JBoss is just the code to load and manage the services. All the services are dynamically loaded and managed and can even be swapped in and out of a running system. They can be mixed and matched as needed, or even replaced entirely.

[Pradeep bhatt]

Thanks Norman

[Pradeep bhatt]

Norman,
If I want to host my custom service , how do I go about it?

[norman richards]

It depends on what the service is. If it is a standalone service or one that matters only to the applications you will be hosting there, then you would normally bundle your service in a SAR file. You expose a management interface as an MBeans declared in your jboss-service.xml file. JBoss will make sure they get started up when the system comes up.

[Pradeep bhatt]

Thanks Norman. Mine is a stand alone service.

JBoss will make sure they get started up when the system comes up.

Does it mean the lifecycle will be managed by JBoss and I need not worry about creating instances ? Do the classes need to implement some interface ?
Suppose I deploy the service and would like the service not to start up next time the server start up, is it possible to do that without actually undeploying the service. Basically the service is deployed and do not want it to start. can this be done? Can I call each MBean a service or is it a set of classes?
I also recd your Xdoclet book, started reading the book. Thanks for writing a great book.
Thanks

[norman richards]

Lifecycle of JBoss services is managed. If you extend ServiceMBeanSupport you will get the state start/stop methods that all services have. I don't know, off the top of my head, if you can deploy a service in the stopped state. You could deploy the service classes and dynamically create and start an MBean managing your service, but I can't give too much advice here. It's not something I have ever needed to do.
Thanks for the comments on the XDoclet book. I hope it helps you out. Feel free to send me comments any time about it. (it's good to get feedback) Amazon reviews are also highly appreciated...

[Gunther Verhemeldonck]

Do you know how to access a service(mbean) from code?
I need to setup a clustered environment and I want to display the name of the server instance that handled the request.