www.pudn.com > 33_online_store.rar > ShoppingCartServlet.java
package shopcart.servlets;
import javax.ejb.*;
import javax.naming.*;
import java.io.*;
import java.util.*;
import java.rmi.*;
import javax.rmi.*;
import java.text.*;
import javax.servlet.*;
import javax.servlet.http.*;
import shopcart.ejbs.*;
import DebugLog;
/**
* This servlet supports four input parameters:
* action: either add, adjust, delete, or view
* item: a text description of the item
* quantity: the number to affect
*
* When accessed the servlet displays the current contents of the cart.
*
*/
public class ShoppingCartServlet extends HttpServlet
implements SingleThreadModel
{
protected Context ctx;
protected ShoppingCartHome home;
protected DebugLog logger;
protected NumberFormat formatter;
public void init(ServletConfig config) throws ServletException
{
super.init(config);
String logServer;
logServer = getInitParameter("logserver");
logger = new DebugLog();
logger.logTo(logServer);
formatter = NumberFormat.getCurrencyInstance();
findHome();
}
protected void findHome()
{
try
{
if(home == null)
{
String homeName;
homeName = getInitParameter("ShoppingCartHome");
if(ctx == null) ctx = new InitialContext();
if(ctx != null)
{
Object ref = ctx.lookup(homeName);
home = (ShoppingCartHome) PortableRemoteObject.narrow(ref,
ShoppingCartHome.class);
}
}
}
catch(Exception exp)
{
ctx = null;
home = null;
logger.log(exp);
}
}
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException
{
HttpSession session; //The current session
String cartName; //The name to use for the cart
ShoppingCart cart=null; //The EJB
Hashtable items; //The current list of items
ShoppingCartItem item; //Used to iterate the list of items
PrintWriter out; //The responses PrintWriter
String action; //Which action was requested
double price=0.0; //Temp variable
int quantity=0; //Temp variable
String desc=null; //Temp variable
String errorMessage = null; //Temp variable
String requestURL; // The URL used to request the servlet
String referer; // URL for the page that made the request
boolean outputCart = true; //Temp variable
session = request.getSession(true);
requestURL = request.getRequestURL().toString();
//See if we are reloading first
referer = request.getParameter("referer");
//Then look for the refering page
if(referer == null)
referer = request.getHeader("Referer");
response.setContentType("text/html");
out = response.getWriter();
items = (Hashtable) session.getAttribute("shoppingcart.items");
if(items==null)
{
session.setAttribute("shoppingcart.items",new Hashtable());
items = (Hashtable) session.getAttribute("shoppingcart.items");
}
action = request.getParameter("action");
try
{
desc = request.getParameter("item");
price = (new Double(request.getParameter("price"))).doubleValue();
quantity = Integer.parseInt(request.getParameter("quantity"));
}
catch(Exception exp)
{
//reset
desc = null;
errorMessage = "No item specified.";
}
if("view".equalsIgnoreCase(action)
||"purchase".equalsIgnoreCase(action))
{
errorMessage = null;
}
if(errorMessage != null)
{
//do nothing, but go to end
}
else if("add".equalsIgnoreCase(action))
{
item = new ShoppingCartItem(desc,price,quantity);
try
{
logger.log("Adding item: "+item);
item = (ShoppingCartItem) items.get(desc);
if(item == null)
{
item = new ShoppingCartItem(desc,price,quantity);
items.put(desc,item);
}
else
{
item.price = price;
item.quantity += quantity;
}
}
catch(Exception exp)
{
logger.log(exp);
errorMessage = "Unable to add item(s).";
}
}
else if("adjust".equalsIgnoreCase(action))
{
item = new ShoppingCartItem(desc,price,quantity);
try
{
item = (ShoppingCartItem) items.get(desc);
if(item != null)
{
item.quantity = quantity;
}
else
{
errorMessage = "Item(s) was not contained in the cart.";
}
}
catch(Exception exp)
{
logger.log(exp);
errorMessage = "Unable to adjust item(s).";
}
}
else if("delete".equalsIgnoreCase(action))
{
item = new ShoppingCartItem(desc,price,quantity);
try
{item = (ShoppingCartItem) items.get(desc);
if(item != null)
{
if(item.quantity > quantity)
{
item.quantity -= quantity;
}
else
{
items.remove(desc);
}
}
else
{
errorMessage = "Item(s) was not contained in the cart.";
}
}
catch(Exception exp)
{
logger.log(exp);
errorMessage = "Unable to remove item(s).";
}
}
else if("purchase".equalsIgnoreCase(action))
{
Hashtable confirmedItems;
confirmedItems =
(Hashtable) session.getAttribute("shoppingcart.itemsToConfirm");
//Try to use the remote user login
cartName = request.getRemoteUser();
if(cartName == null)
{
session = request.getSession(true);
if(session != null) cartName = session.getId();
}
if(home == null) findHome();
//Get the EJB shopping cart
if((home != null)&&(cartName != null))
{
try
{
cart = home.create(cartName);
}
catch(Exception ex)
{
//perhaps home is gone, reset
home = null;
ctx = null;
logger.log(ex);
}
}
if(cart == null)
{
errorMessage = "Unable to load cart.";
}
else
{
logger.log("Cart: "+cart);
}
if(request.getParameter("confirmed")!=null)
{
if(confirmedItems == null)
{
errorMessage = "No items confirmed for purchase.";
}
else
{
String user = request.getParameter("confirmed");
doPurchase(confirmedItems,cart,items
,user,out,requestURL,referer);
outputCart = false;
}
}
else if(errorMessage == null)
{
outputConfirm(items,cart,session,out,requestURL,referer);
outputCart = false;
}
}
else
{
//do nothing, just view
}
if(outputCart && (errorMessage==null))
{
outputCart(items,out,requestURL,referer);
}
else if(errorMessage!=null)
{
outputErrorMessage(out,errorMessage,referer);
}
}
protected void outputErrorMessage(PrintWriter out
,String errorMessage
,String referer)
{
out.println("");
out.println("");
out.println("");
out.println("Shopping Cart");
out.println("");
out.println("");
out.println("");
out.println("");
out.println("");
out.println("");
out.println("| ");
out.println(errorMessage);
if((referer!=null)&&(referer.length()>0))
{
out.print("");
}
out.println(" | ");
out.println("
");
out.println("
");
out.println("");
out.println("");
out.println("");
out.close();
}
protected void outputCart(Hashtable cart
,PrintWriter out
,String requestURL
,String referer)
{
ShoppingCartItem item;
Enumeration items;
float total=0;
items = cart.elements();
out.println("");
out.println("");
out.println("");
out.println("Shopping Cart");
out.println("");
out.println("");
out.println("");
out.println("");
out.println("");
out.println("");
out.println("");
out.println("Shopping Cart");
out.println("Your shopping cart contains the following items:
");
out.println("");
out.println("");
out.println("| Description | ");
out.println("Quantity | ");
out.println("Price | ");
out.println("Total | ");
out.println(" | ");
out.println(" ");
while((items!=null)&&(items.hasMoreElements()))
{
item = (ShoppingCartItem) items.nextElement();
outputItem(item,out,requestURL,referer);
total += item.getTotal();
}
out.println("");
out.println(" | ");
out.println(" | ");
out.println("Total | ");
out.print("");
out.print(formatter.format(total));
out.println(" | ");
out.println(" | ");
out.println(" ");
out.println(" ");
out.println("
");
out.print(" ");
out.println("");
if((referer!=null)&&(referer.length()>0))
{
out.print("");
}
out.println(" | ");
out.println("
");
out.println("
");
out.println("");
out.println("");
out.println("");
out.close();
}
protected void outputItem(ShoppingCartItem item
,PrintWriter out
,String act
,String referer)
{
out.print("");
}
protected void outputConfirm(Hashtable items
,ShoppingCart cart
,HttpSession session
,PrintWriter out
,String requestURL
,String referer)
{
ShoppingCartItem item;
ShoppingCartItem curItem;
Enumeration curItems;
Hashtable itemsToConfirm;
float total=0;
curItems = items.elements();
itemsToConfirm = new Hashtable();
session.setAttribute("shoppingcart.itemsToConfirm",itemsToConfirm);
out.println("");
out.println("");
out.println("");
out.println("Confirm Purchase");
out.println("");
out.println("");
out.println("");
out.println("");
out.println("");
out.println("");
out.println("");
out.println("Confirmation Required");
out.print("Please confirm your purchase of");
out.println(" the following items:
");
out.print("Items that have changed are printed");
out.println(" in blue.");
out.println("");
out.println("");
out.println("| Description | ");
out.println("Quantity | ");
out.println("Price | ");
out.println("Total | ");
out.println(" ");
while((curItems!=null)&&(curItems.hasMoreElements()))
{
curItem = (ShoppingCartItem) curItems.nextElement();
try
{
item = cart.addItem(curItem);
curItem.price = item.price;
curItem.quantity = item.quantity;
itemsToConfirm.put(item.desc,item);
}
catch(Exception exp)
{
logger.log(exp);
item = new ShoppingCartItem("err",0,0);
}
out.println("");
out.print("| ");
out.print(item.desc);
out.println(" | ");
out.print("");
if(item.quantity != curItem.quantity)
out.print("");
out.print(item.quantity);
if(item.quantity != curItem.quantity)
out.print("");
out.println(" | ");
out.print("");
if(item.price != curItem.price)
out.print("");
out.print(formatter.format(item.price));
if(item.price != curItem.price)
out.print("");
out.println(" | ");
out.print("");
out.print(formatter.format(item.getTotal()));
out.println(" | ");
out.println(" ");
total += item.getTotal();
}
out.println("");
out.println(" | ");
out.println(" | ");
out.println("Total | ");
out.print("");
out.print(formatter.format(total));
out.println(" | ");
out.println(" ");
out.println(" ");
out.println("
");
out.print("");
if((referer!=null)&&(referer.length()>0))
{
out.print("");
}
out.println(" | ");
out.println("
");
out.println("
");
out.println("");
out.println("");
out.println("");
out.close();
}
protected void doPurchase(Hashtable items
,ShoppingCart cart
,Hashtable oldCartItems
,String user
,PrintWriter out
,String requestURL
,String referer)
{
ShoppingCartItem item;
ShoppingCartItem curItem;
ShoppingCartItem cartItems[]=null;
int i,max=0;
Enumeration curItems;
float total=0;
boolean failed=false;
boolean badCredit=false;
curItems = items.elements();
try
{
while((curItems!=null)&&(curItems.hasMoreElements()))
{
curItem = (ShoppingCartItem) curItems.nextElement();
cart.addItem(curItem);
}
}
catch(Exception exp)
{
failed = true;
}
if(!failed)
{
try
{
if(!cart.purchaseCart(user)) failed = true;
}
catch(BadCreditException exp)
{
failed = true;
badCredit = true;
}
catch(Exception exp)
{
failed = true;
}
}
if(failed)
{
if(badCredit)
{
outputErrorMessage(out
,"You do not have enough credit to make this purchase."
,referer);
}
else
{
outputErrorMessage(out
,"Server failure, unable to purchase items."
,referer);
}
return;
}
out.println("");
out.println("");
out.println("");
out.println("Purchase Confirmed");
out.println("");
out.println("");
out.println("");
out.println("");
out.println("");
out.println("");
out.println("");
out.println("Purchase Confirmed");
out.print("Thank you for your purchase of the ");
out.println("following items:
");
out.println("");
out.println("");
out.println("| Description | ");
out.println("Quantity | ");
out.println("Price | ");
out.println("Total | ");
out.println(" ");
try
{
cartItems = cart.getItems();
}
catch(Exception exp)
{
}
if(cartItems != null) max = cartItems.length;
for(i=0;i 0)
{
out.println("");
out.print("| ");
out.print(curItem.desc);
out.println(" | ");
out.print("");
out.print(curItem.quantity);
out.println(" | ");
out.print("");
out.print(formatter.format(curItem.price));
out.println(" | ");
out.print("");
out.print(formatter.format(curItem.getTotal()));
out.println(" | ");
out.println(" ");
total += curItem.getTotal();
}
}
out.println("");
out.println(" | ");
out.println(" | ");
out.println("Total | ");
out.print("");
out.print(formatter.format(total));
out.println(" | ");
out.println(" ");
out.println(" ");
if((referer!=null)&&(referer.length()>0))
{
out.print("");
}
out.println(" | ");
out.println("
");
out.println("
");
out.println("");
out.println("");
out.println("");
out.close();
//reset the cart
oldCartItems.clear();
}
}