public class Solution {    /*     * @param s: A string     * @return: A string     */    public static String reverseWords(String s) {        if(s==null || s.length() == 0)  return "";        String[] array = s.split(" ");        StringBuilder sb = new StringBuilder();        for (int i = array.length - 1; i>=0; --i) {            if(!array[i].equals("")){                sb.append(array[i]).append(" ");            }        }        return sb.toString();    }}