private static List<String> getFilesRecursiv(File folder, FileFilter fileNamePattern, boolean recursiv) {
    List<String> list = new LinkedList<String>();
    for (File f : folder.listFiles(fileNamePattern)) {
      list.add(f.getAbsolutePath());
    }
    if (recursiv) {
      for (File childFolder : folder.listFiles(folderFilter)) {
        list.addAll(getFilesRecursiv(childFolder, fileNamePattern, true));
      }
    }
    return list;
  }