逆转字符串leetcode

public class Solution {

    public  String reverseWords(String s) {
          String ans=reverse(s);

         String s2[]=ans.split("\\s+");
         StringBuffer sb=new StringBuffer();
         for(int i=0;i<s2.length;i++)
         {

             sb.append(reverse(s2[i])+" ");

         }

         return  sb.toString().trim();

    }
    private  String reverse(String s)
    {

        int len=s.length();
        char c[]=s.toCharArray();
        for(int i=0;i<len/2;i++)
        {
            char tem=c[i];
            c[i]=c[len-1-i];
            c[len-1-i]=tem;

        }
         return String.valueOf(c);

    }

}