I can just suggest you an idea, But I am sure that it will work, if done correctly.But there may be even other ways better thatn what I say??.
The way i am saying is that You have to touch the source of Jboss. Find the method where it says or prints the statement JBOSS started/ Find the place in the class where it really starts the jboss. At that place try to call you method.
and Similarly there should be another place where it says the ear/war file is successfully deployed.
You can write listeners to listen for specific events. In your case, there are events that are generated when a EAR is deployed.
The link above gives info on how to create a notification. The various Deployer classes in JBoss (Maindeployer,Eardeployer, JarDeployer) send out various events and can be captured .