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keith · Guest

Hi,

I get the following error message when I try to deploy a bean from a
lesson in a book. I've searched the newsgroups, however, haven't
found the cause. Any help would be greatly appreciated.

TIA!
Keith

** Error Message **

java.lang.InstantiationException: ShoppingCart

** Here is some of the code from the jsp page that calls the bean. **

<%@ page errorPage="errorpage.jsp" %>
<%@ page import="myCart.*"%>
<jsp:useBean id="myCart" scope="session" class="ShoppingCart" />

<head> <title>DVD Catalog</title> </head>

<% String id = request.getParameter("itemId"); %>

** Here is the Java code that is being used **
package myCart;
import java.lang.String;
import java.lang.Integer;
import java.lang.Float;
import java.util.Hashtable;
import java.util.Enumeration;

public class ShoppingCart {

protected Hashtable items = new Hashtable();

public void ShoppingCart() {
}

public void addItem(String itemId, String desc, float price, int
quantity) {
String[] item = {itemId, desc, Float.toString(price),
Integer.toString(quantity)};

if (items.containsKey(itemId)) {
String[] tmpItem = (String[])items.get(itemId);
int tmpQuant = Integer.parseInt(tmpItem[3]);
quantity += tmpQuant;
tmpItem[3] = Integer.toString(quantity);
}
else {
items.put(itemId, item);
}
}

public void removeItem(String itemId) {
if (items.containsKey(itemId)) {
items.remove(itemId);
}
}

public void updateQuantity(String itemId, int quantity) {
if (items.contains(itemId)) {
String[] tmpItem = (String[])items.get(itemId);
tmpItem[3] = Integer.toString(quantity);
}
}

public Enumeration getEnumeration() {
return items.elements();
}

public float getCost() {
Enumeration enum = items.elements();
String[] tmpItem;
float totalCost = 0.00f;

while (enum.hasMoreElements()) {
tmpItem = (String[])enum.nextElement();
totalCost += (Integer.parseInt(tmpItem[3]) *
Float.parseFloat(tmpItem[2]));
}
return totalCost;
}

public int getNumOfItems() {
Enumeration enum = items.elements();
String[] tmpItem;
int numOfItems = 0;

while (enum.hasMoreElements()) {
tmpItem = (String[])enum.nextElement();
numOfItems += Integer.parseInt(tmpItem[3]);
}
return numOfItems;
}
}