I am trying to help my friend by creating a part of his on-going project.

What I'm going to do is create a Java parser to break up the Java code into operators, parameters etc to build XML representation.

Next I want to create a code generator to convert the parsed java code to XML conforming to the schema I've created.

Finally I want to use an XML style-sheet to transform the XML into another programming language type.

Basically I just wanted some advice on which methodology/model I should use for planning and developing this project. Is there some benefit to using Agile etc for instance?