code: public static List<Window> windows(String words) {
          StringTokenizer tokenizer = new StringTokenizer(words);
          List<String> list = new ArrayList<String>();
          while (tokenizer.hasMoreTokens())
              list.add(tokenizer.nextToken());
          return windows(list, 5);
      }
docs: Constructs a list of window of size windowSize.
  Note that padding for each window is created as well.
  @param words the words to tokenize and construct windows from
  @return the list of windows for the tokenized string