151. Reverse Words in a String(反转字符串的单词)

Given an input string, reverse the string word by word.

Example:

Input: “the sky is blue”,
Output: “blue is sky the”.
Note:

A word is defined as a sequence of non-space characters.
Input string may contain leading or trailing spaces. However, your reversed string should not contain leading or trailing spaces.
You need to reduce multiple spaces between two words to a single space in the reversed string.

// 华为的机试题就遇到了这个
public class Solution {
    public String reverseWords(String s) {
        String[] strArray=s.trim().split("\\s+");
        StringBuffer sb = new StringBuffer("");
        for(int i=strArray.length-1; i>= 0; i--){
            sb.append(strArray[i]).append(" ");
        }
        String str=sb.toString();
        return str.substring(0,str.length()-1);
    }
}