151. Reverse Words in a String

没什么说的

    public String reverseWords(String s) {
        if(s == null || s.length() == 0) {
            return "";
        }
        s = s.replaceAll(" +", " ");
        System.out.println(s);
        List<String> words = new ArrayList<String>(Arrays.asList(s.split(" ")));
        words.remove("");
        Collections.reverse(words);
        return String.join(" ", words);
    }