旋转单词序列_44

public String ReverseSentence(String str) {
        if (str.length() < 1) {
            return str;
        }

        String res = "", temp = "";
        for (int i = 0; i < str.length(); i++) {
            if (str.charAt(i) != ' ') {
                temp += str.charAt(i);
            } else {
                res = " " + temp + res;
                temp="";
            }
        }

        return temp+res;
    }