public void filterPaths(PathCallback cb){
  String dirPath=_dir.getPath();
  if (!dirPath.endsWith("/")) {
    dirPath+="/";
  }
  filterPaths(_dir,dirPath,cb);
}

public void filterPaths ( PathCallback cb ) { String dirPath = _dir . getPath ( ) ; if ( ! dirPath . endsWith ( "/" ) ) { dirPath += "/" ; } filterPaths ( _dir , dirPath , cb ) ; }
returns the set of files .
