dispatcher.java

《j2ee经典实例详解》的源代码。原书无附带光盘。介绍的是一个在线银行系统的例子。绝对难得

/*
 * 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 com.sun.cb;

import javax.servlet.*;
import javax.servlet.http.*;
import java.util.*;
import java.math.BigDecimal;


public class Dispatcher extends HttpServlet {
    public void doGet(HttpServletRequest request, HttpServletResponse response) {
        HttpSession session = request.getSession();
        ResourceBundle messages =
            (ResourceBundle) session.getAttribute("messages");

        if (messages == null) {
            Locale locale = request.getLocale();
            messages =
                ResourceBundle.getBundle("com.sun.cb.messages.CBMessages",
                    locale);
            session.setAttribute("messages", messages);
        }

        ServletContext context = getServletContext();
        RetailPriceList rpl =
            (RetailPriceList) context.getAttribute("retailPriceList");

        if (rpl == null) {
            try {
                rpl = new RetailPriceList();
                context.setAttribute("retailPriceList", rpl);
            } catch (Exception ex) {
                context.log("Couldn't create price list: " + ex.getMessage());
            }
        }

        ShoppingCart cart = (ShoppingCart) session.getAttribute("cart");

        if (cart == null) {
            cart = new ShoppingCart(rpl);
            session.setAttribute("cart", cart);
        }

        String selectedScreen = request.getServletPath();

        if (selectedScreen.equals("/checkoutForm")) {
            CheckoutFormBean checkoutFormBean =
                new CheckoutFormBean(cart, rpl, messages);

            request.setAttribute("checkoutFormBean", checkoutFormBean);

            try {
                checkoutFormBean.setFirstName(request.getParameter("firstName"));
                checkoutFormBean.setLastName(request.getParameter("lastName"));
                checkoutFormBean.setEmail(request.getParameter("email"));
                checkoutFormBean.setAreaCode(request.getParameter("areaCode"));
                checkoutFormBean.setPhoneNumber(request.getParameter(
                        "phoneNumber"));
                checkoutFormBean.setStreet(request.getParameter("street"));
                checkoutFormBean.setCity(request.getParameter("city"));
                checkoutFormBean.setState(request.getParameter("state"));
                checkoutFormBean.setZip(request.getParameter("zip"));
                checkoutFormBean.setCCNumber(request.getParameter("CCNumber"));
                checkoutFormBean.setCCOption(Integer.parseInt(
                        request.getParameter("CCOption")));
            } catch (NumberFormatException e) {
                // not possible
            }
        }

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

    public void doPost(HttpServletRequest request, HttpServletResponse response) {
        HttpSession session = request.getSession();
        ResourceBundle messages =
            (ResourceBundle) session.getAttribute("messages");

        if (messages == null) {
            Locale locale = request.getLocale();
            messages =
                ResourceBundle.getBundle("com.sun.cb.messages.CBMessages",
                    locale);
            session.setAttribute("messages", messages);
        }

        String selectedScreen = request.getServletPath();
        ServletContext context = getServletContext();

        RetailPriceList rpl =
            (RetailPriceList) context.getAttribute("retailPriceList");

        if (rpl == null) {
            try {
                rpl = new RetailPriceList();
                context.setAttribute("retailPriceList", rpl);
            } catch (Exception ex) {
                context.log("Couldn't create price list: " + ex.getMessage());
            }
        }

        ShoppingCart cart = (ShoppingCart) session.getAttribute("cart");

        if (cart == null) {
            cart = new ShoppingCart(rpl);
            session.setAttribute("cart", cart);
        }

        if (selectedScreen.equals("/orderForm")) {
            cart.clear();

            for (Iterator i = rpl.getItems()
                                 .iterator(); i.hasNext();) {
                RetailPriceItem item = (RetailPriceItem) i.next();
                String coffeeName = item.getCoffeeName();
                BigDecimal pounds = null;

                try {
                    pounds =
                        new BigDecimal(request.getParameter(coffeeName +
                                "_pounds"));
                    pounds = pounds.abs();

                    BigDecimal price =
                        item.getRetailPricePerPound()
                            .multiply(pounds)
                            .setScale(2, BigDecimal.ROUND_HALF_UP);
                    ShoppingCartItem sci =
                        new ShoppingCartItem(item, pounds, price);
                    cart.add(sci);
                } catch (NumberFormatException e) {
                    request.setAttribute("orderError",
                        messages.getString("OrderError"));

                    try {
                        session.setAttribute("cart", null);
                        doGet(request, response);
                    } catch (Exception ex) {
                        ex.printStackTrace();
                    }
                }
            }
        } else if (selectedScreen.equals("/checkoutAck")) {
            CheckoutFormBean checkoutFormBean =
                new CheckoutFormBean(cart, rpl, messages);

            request.setAttribute("checkoutFormBean", checkoutFormBean);

            try {
                checkoutFormBean.setFirstName(request.getParameter("firstName"));
                checkoutFormBean.setLastName(request.getParameter("lastName"));
                checkoutFormBean.setEmail(request.getParameter("email"));
                checkoutFormBean.setAreaCode(request.getParameter("areaCode"));
                checkoutFormBean.setPhoneNumber(request.getParameter(
                        "phoneNumber"));
                checkoutFormBean.setStreet(request.getParameter("street"));
                checkoutFormBean.setCity(request.getParameter("city"));
                checkoutFormBean.setState(request.getParameter("state"));
                checkoutFormBean.setZip(request.getParameter("zip"));
                checkoutFormBean.setCCNumber(request.getParameter("CCNumber"));
                checkoutFormBean.setCCOption(Integer.parseInt(
                        request.getParameter("CCOption")));
            } catch (NumberFormatException e) {
                // not possible
            }

            if (!checkoutFormBean.validate()) {
                try {
                    request.getRequestDispatcher("/checkoutForm")
                           .forward(request, response);
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }
        }

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