See my company (Semantic Designs) Java Front End . It will compute control flowcharts for methods from source code.
The front end of Java is built on top of the DMS Software Reengineering Toolkit , which provides general mechanisms for manipulation (analysis, analysis (for example, extracting control flow charts), transformation and generation).
If you have a specific control flow graph, DMS provides mechanisms that allow you to create a graphical walker, and from this you can intelligently create Java AST, which can then be used to create Java source code. Obviously, your control flow chart will have to use a dictionary that can be easily transformed into Java concepts (for example, no Prolog combines these “operators”), otherwise it will be much more difficult for you to generate the corresponding Java code. If you generated a graph from Java code, this will certainly be the case.