*Reverse Words in a String

题目:

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

For example,
Given s = "the sky is blue",
return "blue is sky the".

Update (2015-02-12):
For C programmers: Try to solve it in-place in O(1) space.

click to show clarification.

Clarification:

• What constitutes a word?
  A sequence of non-space characters constitutes a word.
• Could the input string contain leading or trailing spaces?
  Yes. However, your reversed string should not contain leading or trailing spaces.
• How about multiple spaces between two words?
  Reduce them to a single space in the reversed string.

 

 

public class Solution {
    public String reverseWords(String s) 
    {
        if (s == null || s.length() == 0) 
        {
            return "";
        }
        StringBuilder sb = new StringBuilder();
        String[] string = s.split(" ");
        for (int i= string.length-1;i>=0;i--)
        {
            if(!string[i].equals(""))
            sb.append(string[i]).append(" ");
        }
        
        return sb.length() == 0 ? "" : sb.substring(0, sb.length() - 1);
        
        
    }
}

cleanbook上好像有错