In my project, I used Hibernate2.0 with struts framework.
In hibernate2.0, I used to get the records by using Criteria.
Now I have a problem in sorting.

For example,
private abstract class Book
{
Integer bookId;
String bookName;
}
private abstract class customer
{
Integer customerId;
String customerName;
Book cusomerBookId;
}


In this example,if I want to sort by customerId,customerName, I use

criteria.addOrder(Order.asc(customerId));
criteria.addOrder(Order.asc(customerName));

When I would like to sort by using book Name, I use
criteria.addOrder(Order.asc(cusomerBookId.bookName));

It does not sort,Rather If I give
criteria.addOrder(Order.asc(cusomerBookId));

Like that, then It sorts by bookId

Now How to sort by cusomerBookId.bookName. Is it possible to sort like that?
If possibe how to do it? Kindly explain me.