lintcode-easy-Reverse Words in a String

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