Create Abstract Syntax Tree from Parse Tree in Java

I already have codes for the lexical analyzer and parse tree for microscala grammar. But I need another java code converting the parse tree to abstract tree. There is 6 test files for this grammar and this program should output the abstract tree as per the required format. I will provide the lexical analyzer and parse tree code later upon project acceptance. If required, I do have codes for conversion of parse tree to abstract tree for Clite programming language. But I need it for Microscala language.