5.【字符串】Reverse Words in a String--Accepted Java code

Difficulty: Medium
leetcode url:https://leetcode.com/problems/reverse-words-in-a-string/

public String reverseWords(String s) {        if(s.equals("")) return s;        String sa[]=s.trim().split(" ");        String r="";        for(String s1:sa){            r=s1.equals("") ? r : s1+" "+r;        }        return r.trim();    }