Reverse Words in a String

ReverseWords.java

public String reverseWords(String s) {
  StringBuffer sb = new StringBuffer();
  sb.append("");
  String[] arr = s.trim().split("\\s+");
  for (int i = arr.length - 1; i > -1; i--) {
      sb.append(arr[i]);
      if (i != 0) {
          sb.append(" ");
      }
  }
  return sb.toString();
}