Can Codeql be used to extract backward slice for Java?

Came across Codeql and this library looks promising!

I have to extract:
1. basic def-use chain for intraprocedural and interprocedural analysis with Java. I want to feed:
2. Also I have to extract backward slice

I want to fed the following depending on the need:

- function body of the java source code.
- class
- whole package

Will Codeql work on incomplete code? I don't want three address code as output and I just want to actual sliced code as the output.

Is there a working example in this regard? I would really appreciate your response.