CODE EXAMPLE FOR JAVA

javaparser

public static void main(String[] args) throws Exception {
    // creates an input stream for the file to be parsed
    FileInputStream in = new FileInputStream("test.java");

    CompilationUnit cu;
    try {
        // parse the file
        cu = JavaParser.parse(in);
    } finally {
        in.close();
    }

    // visit and change the methods names and parameters
    new MethodChangerVisitor().visit(cu, null);

    // prints the changed compilation unit
    System.out.println(cu.toString());
}

/**
 * Simple visitor implementation for visiting MethodDeclaration nodes.
 */
private static class MethodChangerVisitor extends VoidVisitorAdapter {

    @Override
    public void visit(MethodDeclaration n, Object arg) {
        // change the name of the method to upper case
        n.setName(n.getName().toUpperCase());

        // create the new parameter
        Parameter newArg = ASTHelper.createParameter(ASTHelper.INT_TYPE, "value");

        // add the parameter to the method
        ASTHelper.addParameter(n, newArg);
    }

}