MySQL™ and JSP™ Web Applications: Data-Driven Programming Using Tomcat and MySQL

Being Stateful

Suppose that you'd like a bean that is a little less flighty than a stateless session bean. You can create a stateful bean instead. For example, extend your cart bean to carry a total of items that you've added to your cart and then compute the tax and the total.

To begin, create a new set of classes based on the name StatefulCart (shown in Listings 17.9, 17.10 and 17.11).

Listing 17.9. StatefulCart.java

package com.bfg.ejb.cart; import javax.ejb.EJBObject; import java.rmi.RemoteException; public interface StatefulCart extends EJBObject { public void clearTotal() throws RemoteException; public void addItem(double price, int quantity) throws RemoteException; public double getTotal() throws RemoteException; public double computeTax(String ...