shoppingcart.java

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/*
 * Copyright (c) 2002 Sun Microsystems, Inc.  All rights reserved.  U.S. 
 * Government Rights - Commercial software.  Government users are subject 
 * to the Sun Microsystems, Inc. standard license agreement and 
 * applicable provisions of the FAR and its supplements.  Use is subject 
 * to license terms.  
 * 
 * This distribution may include materials developed by third parties. 
 * Sun, Sun Microsystems, the Sun logo, Java and J2EE are trademarks 
 * or registered trademarks of Sun Microsystems, Inc. in the U.S. and 
 * other countries.  
 * 
 * Copyright (c) 2002 Sun Microsystems, Inc. Tous droits reserves.
 * 
 * Droits du gouvernement americain, utilisateurs gouvernementaux - logiciel
 * commercial. Les utilisateurs gouvernementaux sont soumis au contrat de 
 * licence standard de Sun Microsystems, Inc., ainsi qu'aux dispositions 
 * en vigueur de la FAR (Federal Acquisition Regulations) et des 
 * supplements a celles-ci.  Distribue par des licences qui en 
 * restreignent l'utilisation.
 * 
 * Cette distribution peut comprendre des composants developpes par des 
 * tierces parties. Sun, Sun Microsystems, le logo Sun, Java et J2EE 
 * sont des marques de fabrique ou des marques deposees de Sun 
 * Microsystems, Inc. aux Etats-Unis et dans d'autres pays.
 */


package cart;

import java.util.*;
import database.BookDetails;
 
public class ShoppingCart {
    HashMap items = null;
    int numberOfItems = 0;

    public ShoppingCart() {
        items = new HashMap();
    }

    public synchronized void add(String bookId, BookDetails book) {
        if(items.containsKey(bookId)) {
            ShoppingCartItem scitem = (ShoppingCartItem) items.get(bookId);
            scitem.incrementQuantity();
        } else {
            ShoppingCartItem newItem = new ShoppingCartItem(book);
            items.put(bookId, newItem);
        }

        numberOfItems++;
     }

    public synchronized void remove(String bookId) {
        if(items.containsKey(bookId)) {
            ShoppingCartItem scitem = (ShoppingCartItem) items.get(bookId);
            scitem.decrementQuantity();

            if(scitem.getQuantity() <= 0)
                items.remove(bookId);

            numberOfItems--;
        }
    }

    public synchronized Collection getItems() {
        return items.values();
    }

    protected void finalize() throws Throwable {
        items.clear();
    }

    public synchronized int getNumberOfItems() {
        return numberOfItems;
    }
    public synchronized double getTotal() {
        double amount = 0.0;

        for(Iterator i = getItems().iterator(); i.hasNext(); ) {
            ShoppingCartItem item = (ShoppingCartItem) i.next();
            BookDetails bookDetails = (BookDetails) item.getItem();

            amount += item.getQuantity() * bookDetails.getPrice();
        }
        return roundOff(amount);
    }

    private double roundOff(double x) {
        long val = Math.round(x*100); // cents
        return val/100.0;
    }

    public synchronized void clear() {
        System.err.println("Clearing cart.");
        items.clear();
        numberOfItems = 0;
    }
}