www.pudn.com > bookstore2.rar > Dispatcher.java

/* 
 * Copyright (c) 2005 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) 2005 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 dispatcher; 
 
import javax.servlet.*; 
import javax.servlet.http.*; 
import java.util.*; 
import cart.ShoppingCart; 
import database.*; 
import exception.*; 
 
 
public class Dispatcher extends HttpServlet { 
    public void doGet(HttpServletRequest request, HttpServletResponse response) { 
        String bookId = null; 
        String clear = null; 
        BookDetails book = null; 
        BookDBAO bookDBAO = 
            (BookDBAO) getServletContext() 
                           .getAttribute("bookDBAO"); 
        HttpSession session = request.getSession(); 
        String selectedScreen = request.getServletPath(); 
        ShoppingCart cart = (ShoppingCart) session.getAttribute("cart"); 
 
        if (cart == null) { 
            cart = new ShoppingCart(); 
            session.setAttribute("cart", cart); 
        } 
 
        if (selectedScreen.equals("/bookcatalog")) { 
            bookId = request.getParameter("Add"); 
 
            if (!bookId.equals("")) { 
                try { 
                    book = bookDBAO.getBookDetails(bookId); 
                    cart.add(bookId, book); 
                } catch (BookNotFoundException ex) { 
                    // not possible 
                } 
            } 
        } else if (selectedScreen.equals("/bookshowcart")) { 
            bookId = request.getParameter("Remove"); 
 
            if (bookId != null) { 
                cart.remove(bookId); 
            } 
 
            clear = request.getParameter("Clear"); 
 
            if ((clear != null) && clear.equals("clear")) { 
                cart.clear(); 
            } 
        } else if (selectedScreen.equals("/bookreceipt")) { 
            // Update the inventory 
            try { 
                bookDBAO.buyBooks(cart); 
            } catch (OrderException ex) { 
                selectedScreen = "/bookordererror"; 
            } 
        } 
 
        String screen = selectedScreen + ".jsp"; 
 
        try { 
            request.getRequestDispatcher(screen) 
                   .forward(request, response); 
        } catch (Exception ex) { 
            ex.printStackTrace(); 
        } 
    } 
 
    public void doPost(HttpServletRequest request, HttpServletResponse response) { 
        String screen = request.getServletPath() + ".jsp"; 
 
        try { 
            request.getRequestDispatcher(screen) 
                   .forward(request, response); 
        } catch (Exception ex) { 
            ex.printStackTrace(); 
        } 
    } 
}