This week's book giveaway is in the OCMJEA forum. We're giving away four copies of OCM Java EE 6 Enterprise Architect Exam Guide and have Paul Allen & Joseph Bambara on-line! See this thread for details.
I agree with Anupam. Either make your CTVo class implement the Comparable interface, or make a custom Comparator which you will pass to sort(List list, Comparator c). Look for documentation about those classes, and try to figure out yourself how it works. Ask more if you still don't understand how Comparator/Comparable work Here is a place you could start with : http://java.sun.com/docs/books/tutorial/collections/interfaces/order.html