Code to parse java code

Question

anyone know where we can get the code that parses the Java code that we put here ?
i was thinking it would be a good base to use as a pre-compiler project - so we can have pre-compiler flags like in c - say to include logging ...
example of the code formatting at work:
class Rename{
  * Rename a file from command line,
  * args[0] is the existing file name
  * args[1] is the new file name
  public static void main (String[] args)
   try{
    java.io.File fExisting = new java.io.File(args[0]);   
    java.io.File fNew = new java.io.File(args[1]);
    if(!fExisting.exists()){
     System.out.println("Rename will fail as source does not  exist. Exiting");
     return;
    if(fNew.exists()){
     System.out.println("Rename might fail as target already exits - delete it first ");
    System.out.println("attempt rename :\n" + fExisting.getAbsolutePath() + "\n to:\n" + fNew.getAbsolutePath() );
    boolean b = fExisting.renameTo(fNew);
    if(b){
     System.out.println("Done ok ");
    }else{
     System.out.println("rename failed ");
   }catch(Throwable e){
    System.out.println("Could not rename " + e);
    e.printStackTrace();
synchrozied (objSync){
try{
  while(bPause){
   Thread.sleep(250);  
  }catch(Throwable e){
   //can ignore
}would be a nice source forge project - unless there is already one out there

Answer 1

Try this link from Javaranch - I started reading it, but got distracted and did not pursue it very far. It's about JFlex parser and an example of parsing java code is provided or linked to:
http://www.javaranch.com/journal/2008/04/Journal200804.jsp#a4
Look for the section titled: "Handling Uncommon File Formats - Introducing Lexers"