dispatcher.java

j2ee API 开发重要工具 免费下载 欢迎使用

/*
 * 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 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;
      BookDetails book = null;
      String clear = 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);
            if ( book.getOnSale() ) {
              double sale = book.getPrice() * .85;
              Float salePrice = new Float(sale);
              book.setPrice(salePrice.floatValue());
            }
            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) {

          try {
              request.getRequestDispatcher("/bookordererror.jsp").forward(request, response);
          } catch(Exception e) {
              e.printStackTrace();
          }
        }

    }


    try {
        request.getRequestDispatcher("/template/template.jsp").forward(request, response);
    } catch(Exception ex) {
        ex.printStackTrace();
    }
  }

  public void doPost(HttpServletRequest request, HttpServletResponse response) {     
    request.setAttribute("selectedScreen", request.getServletPath());

    try {
        request.getRequestDispatcher("/template/template.jsp").forward(request, response);
    } catch(Exception ex) {
        ex.printStackTrace();
    }
  }
}