code: public int compare(T o1, T o2) {
  	if(o1 == o2)   return 0;
  	String str1 = (o1 == null) ? "null" : o1.toString(); 
  	String str2 = (o2 == null) ? "null" : o2.toString();
  	return str1.compareTo(str2);
      }
docs: Compares its two arguments for order.
  Returns a negative integer, zero, or a positive integer as the
  string representation of the first argument is less than, equal
  to, or greater to the string representation of the second.