AST generation with Sonar Toolkit

What I want to do:
AST generation with Sonar for a java class.

Why?
I want to see how an AST looks like when its generated through sonar for learning purposes.

What I did so far
I created a project where I can configure and use the sonar toolkit. And hopefully, somehow use that to generate an AST. However, I cannot find the ConfigurationModel for java anywhere.
Does anyone have any tips to help me further? Perhaps where I can look or what I can do to achieve my goal?