public static List<File> scan(List<String> roots,String[] includes,String[] excludes){
  List<File> files=new ArrayList<File>();
  for (  String root : roots) {
    files.addAll(FileUtils.scan(new File(root),includes,excludes));
  }
  return files;
}

public static List < File > scan ( List < String > roots , String [ ] includes , String [ ] excludes ) { List < File > files = new ArrayList < File > ( ) ; for ( String root : roots ) { files . addAll ( FileUtils . scan ( new File ( root ) , includes , excludes ) ) ; } return files ; }
scans a set of directories
