How to manage user and domain in Apache James Server from Grails application or Java application

I am using James Server along with a Grails application.

I am currently manually adding a Domain and User to the James Server and I want to automate this process through a Grails application so that I do not need to add the Domain and User by running the command on the James Server command line.

I was able to get James up and running and parse the mail in the James' inbox from the Grails application and everything is perfect.

I searched the web and found out that there is no API for this. The only ways are CLI which I already do and the other JMX

I've searched for JMX and a plugin in Grails but couldn't implement it.

Please help me to do this with JMX or by providing some other measures.

I ran into calling an external process in Groovy but didn't work.