谢谢大家帮我看一下pet store 中的href 语法,究竟是如何实现页面转向

Question

看下用的是什么标签，如果是Struts标签的话，此处是全局跳转

Answer 1

大师,快帮忙看看,下面这些链接是不是很象这个什么Struts,是用于掩藏链接地址的一种手段吗  <a href="category?category_id=FISH" onmouseover="img_on('fish')" onmouseout="img_off('fish')"><img src="/estore/images/fish.gif" border="0" name="img_fish"></a>
      <img src="/estore/images/separator.gif" border="0">
      <a href="category?category_id=DOGS" onmouseover="img_on('dogs')" onmouseout="img_off('dogs')"><img src="/estore/images/dogs.gif" border="0" name="img_dogs"></a>
      <img src="/estore/images/separator.gif" border="0">
      <a href="category?category_id=REPTILES" onmouseover="img_on('reptiles')" onmouseout="img_off('reptiles')"><img src="/estore/images/reptiles.gif" border="0" name="img_reptiles"></a>
      <img src="/estore/images/separator.gif" border="0">
      <a href="category?category_id=CATS" onmouseover="img_on('cats')" onmouseout="img_off('cats')"><img src="/estore/images/cats.gif" border="0" name="img_cats"></a>
      <img src="/estore/images/separator.gif" border="0">
      <a href="category?category_id=BIRDS" onmouseover="img_on('birds')" onmouseout="img_off('birds')"><img src="/estore/images/birds.gif" border="0" name="img_birds"></a>

Answer 2

谢谢.可我还是不怎么明白,哎,基础太差了,几位前辈可以给我举一个简单范例吗比如说 , a.jsp 如何 调用 b.jsp , 关键是这个传递的参数究竟是在哪里设定的, 我应该如何去控制

Answer 3

http://community.csdn.net/Expert/topic/5756/5756718.xml?temp=.5951349

Answer 4

对不起,我还是闹不明白,能不能再多推荐一点资料,我再举一个例子吧 <a href="/estore/control/signin" onmouseover="img_on('signin')" onmouseout="img_off('signin')"><img src="/estore/images/sign-in.gif" border="0" name="img_signin"></a>这是打开登陆界面,根下有signin.jsp文件,被调用了,可我不明白的是,这些*.jsp是如何组织起来的,是在哪里定义 "/estore/control/signin" = signin.jsp

Answer 5

你看你的web.config 在里面配置的 我估计是用到了struts 所有的请求都到了ActionServlet
然后在看看你的 struts-config 里面是不是有个signin 它的redirect到了 signin.jsp？

Answer 6

我用的是 SUN公司的 pet store 1.1.2 版,这是一个J2EE的工程DEMO主体结构是 EJB包 + jsp包 , 发布的是*.ear ,也就是 *.jar + *.war
与struts结构是完全不同的另一种结构
 
jsp里面通过JNDI,可以找到并调用EJB
我现在头疼的是jsp是如何找到并调用jsp,怎样实现的

Answer 7

这个东西没接触过，，，，我都一年没接触java了  你还是看看web.config
或者把web.config发出来看看  肯定能找到他调用的路径的

Answer 8

谢谢大哥,没有web.config文件,看web.xml可以吗,这是前台的<?xml version="1.0" encoding="ISO-8859-1"?><!DOCTYPE web-app PUBLIC '-//Sun Microsystems, Inc.//DTD Web Application 2.2//EN' 'http://java.sun.com/j2ee/dtds/web-app_2.2.dtd'><web-app>
  <display-name>WebTier</display-name>
  <description>Web Tier DD for the PetStore application</description>  <servlet>
    <servlet-name>webTierEntryPoint</servlet-name>
    <display-name>centralServlet</display-name>
    <description>no description</description>
    <servlet-class>com.sun.j2ee.blueprints.petstore.control.web.MainServlet</servlet-class>
  </servlet>
  <servlet-mapping>
    <servlet-name>webTierEntryPoint</servlet-name>
    <url-pattern>/control/*</url-pattern>
  </servlet-mapping>  <servlet>
    <servlet-name>populateServlet</servlet-name>
    <display-name>Populate Servlet</display-name>
    <description>no description</description>
    <servlet-class>com.sun.j2ee.blueprints.tools.populate.web.PopulateServlet</servlet-class>
  </servlet>
  <servlet-mapping>
    <servlet-name>populateServlet</servlet-name>
    <url-pattern>/populate</url-pattern>
  </servlet-mapping>  <session-config>
    <session-timeout>54</session-timeout>
  </session-config>  <welcome-file-list>
    <welcome-file>index.html</welcome-file>
  </welcome-file-list>
  <resource-ref>
    <res-ref-name>jdbc/EstoreDataSource</res-ref-name>
    <res-type>javax.sql.DataSource</res-type>
    <res-auth>Container</res-auth>
  </resource-ref>  <env-entry>
    <env-entry-name>ejb/catalog/CatalogDAOClass</env-entry-name>
    <env-entry-type>java.lang.String</env-entry-type>
    <env-entry-value>com.sun.j2ee.blueprints.shoppingcart.catalog.dao.CatalogDAOImpl</env-entry-value>
  </env-entry>
  <env-entry>
    <env-entry-name>ejb/profilemgr/ProfileMgrDAOClass</env-entry-name>
    <env-entry-type>java.lang.String</env-entry-type>
    <env-entry-value>com.sun.j2ee.blueprints.personalization.profilemgr.dao.ProfileMgrDAOImpl</env-entry-value>
  </env-entry>
  <env-entry>
    <env-entry-name>server/ServerType</env-entry-name>
    <env-entry-value>Java 2 Enterprise Edition Reference Implementation</env-entry-value>
    <env-entry-type>java.lang.String</env-entry-type>
  </env-entry>  <ejb-ref>
    <ejb-ref-name>ejb/catalog/Catalog</ejb-ref-name>
    <ejb-ref-type>Session</ejb-ref-type>
    <home>com.sun.j2ee.blueprints.shoppingcart.catalog.ejb.CatalogHome</home>
    <remote>com.sun.j2ee.blueprints.shoppingcart.catalog.ejb.Catalog</remote>
  </ejb-ref>
  <ejb-ref>
    <ejb-ref-name>ejb/cart/Cart</ejb-ref-name>
    <ejb-ref-type>Session</ejb-ref-type>
    <home>com.sun.j2ee.blueprints.shoppingcart.cart.ejb.ShoppingCartHome</home>
    <remote>com.sun.j2ee.blueprints.shoppingcart.cart.ejb.ShoppingCart</remote>
  </ejb-ref>
  <ejb-ref>
    <ejb-ref-name>ejb/customer/Customer</ejb-ref-name>
    <ejb-ref-type>Session</ejb-ref-type>
    <home>com.sun.j2ee.blueprints.customer.customer.ejb.CustomerHome</home>
    <remote>com.sun.j2ee.blueprints.customer.customer.ejb.Customer</remote>
  </ejb-ref>
  <ejb-ref>
    <ejb-ref-name>ejb/profilemgr/ProfileMgr</ejb-ref-name>
    <ejb-ref-type>Entity</ejb-ref-type>
    <home>com.sun.j2ee.blueprints.personalization.profilemgr.ejb.ProfileMgrHome</home>
    <remote>com.sun.j2ee.blueprints.personalization.profilemgr.ejb.ProfileMgr</remote>
  </ejb-ref>
  <ejb-ref>
    <ejb-ref-name>ejb/scc/Scc</ejb-ref-name>
    <ejb-ref-type>Session</ejb-ref-type>
    <home>com.sun.j2ee.blueprints.petstore.control.ejb.ShoppingClientControllerHome</home>
    <remote>com.sun.j2ee.blueprints.petstore.control.ejb.ShoppingClientController</remote>
  </ejb-ref>
  <ejb-ref>
    <ejb-ref-name>ejb/inventory/Inventory</ejb-ref-name>
    <ejb-ref-type>Entity</ejb-ref-type>
    <home>com.sun.j2ee.blueprints.inventory.ejb.InventoryHome</home>
    <remote>com.sun.j2ee.blueprints.inventory.ejb.Inventory</remote>
  </ejb-ref>
</web-app>

Answer 9

嘿嘿 不好意思 .net上是web.config....忘记了 
你看这段 <servlet>
    <servlet-name>webTierEntryPoint</servlet-name>
    <display-name>centralServlet</display-name>
    <description>no description</description>
    <servlet-class>com.sun.j2ee.blueprints.petstore.control.web.MainServlet</servlet-class>
  </servlet>
  <servlet-mapping>
    <servlet-name>webTierEntryPoint</servlet-name>
    <url-pattern>/control/*</url-pattern>
  </servlet-mapping>
 <url-pattern>/control/*</url-pattern> 表示 你所有"control/包含的请求都交给com.sun.j2ee.blueprints.petstore.control.web.MainServlet来处理 包括你的
“/estore/control/signin”
然后 MainServlet你的init方法肯定也解析了一个xml 那个xml 里面 就有一个配置 名字是signin  路径就应该是signin.jsp了 大致就是这个意思了

Answer 10

谢谢,帮忙再看看,这是 MainServlet里的init方法,还有另两个XML文件,其中确实有配置signin.jsp的路径, 可我还是难以理解究竟是如何用法,可以讲的详细点吗public void init() {
        Debug.println("MainServlet: Initializing");
        String requestMappingsURL = null;
        try {
            requestMappingsURL = getServletContext().getResource("/WEB-INF/xml/requestmappings.xml").toString();
        } catch (java.net.MalformedURLException ex) {
            Debug.println("ScreenFlowManager: initializing ScreenFlowManager malformed URL exception: " + ex);
        }
       urlMappings = ScreenFlowXmlDAO.loadRequestMappings(requestMappingsURL);
       getServletContext().setAttribute(WebKeys.URLMappingsKey, urlMappings);
       Debug.println("MainServlet: loaded urlMappings");
       String serverType = null;
       try {
            InitialContext ic = new InitialContext();
            serverType = (String)ic.lookup(JNDINames.SERVER_TYPE);
            getServletContext().setAttribute(WebKeys.ServerTypeKey, serverType);
        } catch (NamingException ex) {
            Debug.println("Server Type not specified in deployment descriptor: using default J2ee Security Adapter");
        }
        getScreenFlowManager();
        getRequestProcessor();
        Debug.println("MainServlet: Initialization complete");
    }--------------------------requestmappings.xml------------------------
<?xml version="1.0" encoding="ISO-8859-1"?><request-mappings>
    <screen-definition url="/WEB-INF/xml/screendefinitions.xml" language="en_US"/>
    <screen-definition url="/WEB-INF/xml/ja/screendefinitions.xml" language="ja_JP"/>    <default-screen>MAIN</default-screen>
    <signin-screen>SIGN_IN</signin-screen>
    <signin-error-screen>SIGN_IN_ERROR</signin-error-screen>
    <url-mapping url="/main" screen="MAIN"/>
    <url-mapping url="/search" screen="SEARCH"/>
    <url-mapping url="/category" screen="CATEGORY"/>
    <url-mapping url="/product" screen="PRODUCT"/>
    <url-mapping url="/catalog" screen="CATALOG"/>
    <url-mapping url="/error" screen="ERROR"/>
    <url-mapping url="/accountcreated" screen="ACCOUNT_CREATED"/>
    <url-mapping url="/createnewaccount" screen="CREATE_ACCOUNT"/>
    <url-mapping url="/editaccount" screen="EDIT_ACCOUNT" requiresSignin="true"/>
    <url-mapping url="/accountedited" screen="ACCOUNT_UPDATED"/>    <url-mapping url="/signin" screen ="SIGN_IN_SUCCESS" requiresSignin="true"/>
    <url-mapping url="/signout" screen="SIGN_OUT" useRequestHandler="true" >
      <request-handler-class>com.sun.j2ee.blueprints.petstore.control.web.handlers.SignoutHandler</request-handler-class>
    </url-mapping>    <url-mapping url="/language" screen="MAIN" useRequestHandler="true" >
      <request-handler-class>com.sun.j2ee.blueprints.petstore.control.web.handlers.LanguageHandler</request-handler-class>
    </url-mapping>    <url-mapping url="/help" screen="HELP"/>
    <url-mapping url="/checkout" screen="CHECK_OUT"/>
    <url-mapping url="/placeorder" screen="PLACE_ORDER" requiresSignin="true"/>
    <url-mapping url="/productdetails" screen="PRODUCT_DETAILS"/>
    <url-mapping url="/verifysignin" screen="SIGN_IN_SUCCESS" useRequestHandler="true" useFlowHandler="true">
        <request-handler-class>com.sun.j2ee.blueprints.petstore.control.web.handlers.SigninHandler</request-handler-class>
        <flow-handler class="com.sun.j2ee.blueprints.petstore.control.web.handlers.SigninFlowHandler">
            <handler-result result="2" screen="SIGN_IN_ERROR"/>
            <handler-result result="1" screen="SIGN_IN_SUCCESS"/>
        </flow-handler>
   </url-mapping>
    <url-mapping url="/validateshippinginformation" useRequestHandler="true" useFlowHandler="true" requiresSignin="true">
        <request-handler-class>com.sun.j2ee.blueprints.petstore.control.web.handlers.ExtractShippingInformationHandler</request-handler-class>
        <flow-handler class="com.sun.j2ee.blueprints.petstore.control.web.handlers.ShippingFlowHandler">
            <handler-result result="1" screen="VALIDATE_BILLING_INFORMATION"/>
            <handler-result result="2" screen="MISSING_FORM_DATA"/>
      </flow-handler>
   </url-mapping>    <url-mapping url="/validatebillinginformation" screen="VALIDATE_BILLING_INFORMATION" useRequestHandler="true" useFlowHandler="true" requiresSignin="true">
       <request-handler-class>com.sun.j2ee.blueprints.petstore.control.web.handlers.ExtractBillingInformationHandler</request-handler-class>
       <flow-handler class="com.sun.j2ee.blueprints.petstore.control.web.handlers.AccountFlowHandler">
         <handler-result result="1" screen="ENTER_SHIPPING_INFORMATION"/>
         <handler-result result="2" screen="VALIDATE_BILLING_INFORMATION"/>
         <handler-result result="3" screen="MISSING_FORM_DATA"/>
      </flow-handler>
   </url-mapping>
    <url-mapping url="/entershippingaddress" useRequestHandler="true" useFlowHandler="true" requiresSignin="true">
     <request-handler-class>com.sun.j2ee.blueprints.petstore.control.web.handlers.ExtractShippingInformationHandler</request-handler-class>
       <flow-handler class="com.sun.j2ee.blueprints.petstore.control.web.handlers.ShippingFlowHandler">
         <handler-result result="1" screen="ENTER_SHIPPING_INFORMATION"/>
         <handler-result result="2" screen="MISSING_FORM_DATA"/>
      </flow-handler>
    </url-mapping>    <url-mapping url="/validatenewaccount" screen="ACCOUNT_CREATED" useRequestHandler="true" useFlowHandler="true">
       <request-handler-class>com.sun.j2ee.blueprints.petstore.control.web.handlers.AccountHandler</request-handler-class>
       <flow-handler class="com.sun.j2ee.blueprints.petstore.control.web.handlers.AccountFlowHandler">
         <handler-result result="1" screen="ACCOUNT_CREATED"/>
         <handler-result result="2" screen="ACCOUNT_CREATED"/>
         <handler-result result="3" screen="MISSING_FORM_DATA"/>
      </flow-handler>
   </url-mapping>    <url-mapping url="/updateaccount" screen="ACCOUNT_UPDATED" useRequestHandler="true">
      <request-handler-class>com.sun.j2ee.blueprints.petstore.control.web.handlers.AccountHandler</request-handler-class>
    </url-mapping>    <url-mapping url="/missingformdata" screen="MISSING_FORM_DATA"/>
    <url-mapping url="/commitorder" useRequestHandler="true" screen="COMMIT_ORDER" requiresSignin="true">
      <request-handler-class>com.sun.j2ee.blueprints.petstore.control.web.handlers.OrderHandler</request-handler-class>
    </url-mapping>    <url-mapping url="/cart" useRequestHandler="true" screen="CART">
      <request-handler-class>com.sun.j2ee.blueprints.petstore.control.web.handlers.CartHandler</request-handler-class>
    </url-mapping>    <exception-mapping exception-class="com.sun.j2ee.blueprints.petstore.control.exceptions.SigninFailedException" screen="SIGN_IN_ERROR"/>
    <exception-mapping exception-class="com.sun.j2ee.blueprints.petstore.control.exceptions.DuplicateAccountException" screen="DUPLICATE_ACCOUNT"/>
    <exception-mapping exception-class="com.sun.j2ee.blueprints.petstore.control.exceptions.GeneralFailureException" screen="ERROR"/></request-mappings >

Answer 11

----------------------screendefinitions.xml------------------------
<?xml version="1.0" encoding="ISO-8859-1"?><request-mappings>
    <screen-definition url="/WEB-INF/xml/screendefinitions.xml" language="en_US"/>
    <screen-definition url="/WEB-INF/xml/ja/screendefinitions.xml" language="ja_JP"/>    <default-screen>MAIN</default-screen>
    <signin-screen>SIGN_IN</signin-screen>
    <signin-error-screen>SIGN_IN_ERROR</signin-error-screen>
    <url-mapping url="/main" screen="MAIN"/>
    <url-mapping url="/search" screen="SEARCH"/>
    <url-mapping url="/category" screen="CATEGORY"/>
    <url-mapping url="/product" screen="PRODUCT"/>
    <url-mapping url="/catalog" screen="CATALOG"/>
    <url-mapping url="/error" screen="ERROR"/>
    <url-mapping url="/accountcreated" screen="ACCOUNT_CREATED"/>
    <url-mapping url="/createnewaccount" screen="CREATE_ACCOUNT"/>
    <url-mapping url="/editaccount" screen="EDIT_ACCOUNT" requiresSignin="true"/>
    <url-mapping url="/accountedited" screen="ACCOUNT_UPDATED"/>    <url-mapping url="/signin" screen ="SIGN_IN_SUCCESS" requiresSignin="true"/>
    <url-mapping url="/signout" screen="SIGN_OUT" useRequestHandler="true" >
      <request-handler-class>com.sun.j2ee.blueprints.petstore.control.web.handlers.SignoutHandler</request-handler-class>
    </url-mapping>    <url-mapping url="/language" screen="MAIN" useRequestHandler="true" >
      <request-handler-class>com.sun.j2ee.blueprints.petstore.control.web.handlers.LanguageHandler</request-handler-class>
    </url-mapping>    <url-mapping url="/help" screen="HELP"/>
    <url-mapping url="/checkout" screen="CHECK_OUT"/>
    <url-mapping url="/placeorder" screen="PLACE_ORDER" requiresSignin="true"/>
    <url-mapping url="/productdetails" screen="PRODUCT_DETAILS"/>
    <url-mapping url="/verifysignin" screen="SIGN_IN_SUCCESS" useRequestHandler="true" useFlowHandler="true">
        <request-handler-class>com.sun.j2ee.blueprints.petstore.control.web.handlers.SigninHandler</request-handler-class>
        <flow-handler class="com.sun.j2ee.blueprints.petstore.control.web.handlers.SigninFlowHandler">
            <handler-result result="2" screen="SIGN_IN_ERROR"/>
            <handler-result result="1" screen="SIGN_IN_SUCCESS"/>
        </flow-handler>
   </url-mapping>
    <url-mapping url="/validateshippinginformation" useRequestHandler="true" useFlowHandler="true" requiresSignin="true">
        <request-handler-class>com.sun.j2ee.blueprints.petstore.control.web.handlers.ExtractShippingInformationHandler</request-handler-class>
        <flow-handler class="com.sun.j2ee.blueprints.petstore.control.web.handlers.ShippingFlowHandler">
            <handler-result result="1" screen="VALIDATE_BILLING_INFORMATION"/>
            <handler-result result="2" screen="MISSING_FORM_DATA"/>
      </flow-handler>
   </url-mapping>    <url-mapping url="/validatebillinginformation" screen="VALIDATE_BILLING_INFORMATION" useRequestHandler="true" useFlowHandler="true" requiresSignin="true">
       <request-handler-class>com.sun.j2ee.blueprints.petstore.control.web.handlers.ExtractBillingInformationHandler</request-handler-class>
       <flow-handler class="com.sun.j2ee.blueprints.petstore.control.web.handlers.AccountFlowHandler">
         <handler-result result="1" screen="ENTER_SHIPPING_INFORMATION"/>
         <handler-result result="2" screen="VALIDATE_BILLING_INFORMATION"/>
         <handler-result result="3" screen="MISSING_FORM_DATA"/>
      </flow-handler>
   </url-mapping>
    <url-mapping url="/entershippingaddress" useRequestHandler="true" useFlowHandler="true" requiresSignin="true">
     <request-handler-class>com.sun.j2ee.blueprints.petstore.control.web.handlers.ExtractShippingInformationHandler</request-handler-class>
       <flow-handler class="com.sun.j2ee.blueprints.petstore.control.web.handlers.ShippingFlowHandler">
         <handler-result result="1" screen="ENTER_SHIPPING_INFORMATION"/>
         <handler-result result="2" screen="MISSING_FORM_DATA"/>
      </flow-handler>
    </url-mapping>    <url-mapping url="/validatenewaccount" screen="ACCOUNT_CREATED" useRequestHandler="true" useFlowHandler="true">
       <request-handler-class>com.sun.j2ee.blueprints.petstore.control.web.handlers.AccountHandler</request-handler-class>
       <flow-handler class="com.sun.j2ee.blueprints.petstore.control.web.handlers.AccountFlowHandler">
         <handler-result result="1" screen="ACCOUNT_CREATED"/>
         <handler-result result="2" screen="ACCOUNT_CREATED"/>
         <handler-result result="3" screen="MISSING_FORM_DATA"/>
      </flow-handler>
   </url-mapping>    <url-mapping url="/updateaccount" screen="ACCOUNT_UPDATED" useRequestHandler="true">
      <request-handler-class>com.sun.j2ee.blueprints.petstore.control.web.handlers.AccountHandler</request-handler-class>
    </url-mapping>    <url-mapping url="/missingformdata" screen="MISSING_FORM_DATA"/>
    <url-mapping url="/commitorder" useRequestHandler="true" screen="COMMIT_ORDER" requiresSignin="true">
      <request-handler-class>com.sun.j2ee.blueprints.petstore.control.web.handlers.OrderHandler</request-handler-class>
    </url-mapping>    <url-mapping url="/cart" useRequestHandler="true" screen="CART">
      <request-handler-class>com.sun.j2ee.blueprints.petstore.control.web.handlers.CartHandler</request-handler-class>
    </url-mapping>    <exception-mapping exception-class="com.sun.j2ee.blueprints.petstore.control.exceptions.SigninFailedException" screen="SIGN_IN_ERROR"/>
    <exception-mapping exception-class="com.sun.j2ee.blueprints.petstore.control.exceptions.DuplicateAccountException" screen="DUPLICATE_ACCOUNT"/>
    <exception-mapping exception-class="com.sun.j2ee.blueprints.petstore.control.exceptions.GeneralFailureException" screen="ERROR"/></request-mappings >

Answer 12

----------------------------screendefinitions.xml-------------------------------
<screen>
    <screen-name>SIGN_IN</screen-name>
    <parameter key="HtmlTitle" value="Sign In" direct="true"/>
    <parameter key="HtmlBanner" value="/banner.jsp" direct="false"/>
    <parameter key="HtmlTopIndex" value="/topindex.jsp" direct="false"/>
    <parameter key="HtmlBody" value="/signin.jsp" direct="false"/>
    <parameter key="HtmlFooter" value="/footer.jsp" direct="false"/>
    <parameter key="Annotation" value="/estore/annotation/ann_security_j2ee.jsp" direct="true"/>
   </screen>

Answer 13

你把 整个MainServlet都贴出来 
因为跳转不可能在init里面的 
我没调试也不知道requestMappingsURL = getServletContext().getResource("/WEB-INF/xml/requestmappings.xml").toString();
 这个到底读出来的是什么。。

Answer 14

--------------------MainServlet.java------------------------------
/*
 * $Id: MainServlet.java,v 1.14.4.8 2001/03/15 00:40:02 brydon Exp $
 * Copyright 2001 Sun Microsystems, Inc. All rights reserved.
 * Copyright 2001 Sun Microsystems, Inc. Tous droits r?erv?.
 */package com.sun.j2ee.blueprints.petstore.control.web;import javax.servlet.ServletException;
import javax.servlet.ServletContext;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpSession;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.PrintWriter;
import java.io.OutputStreamWriter;
import java.beans.Beans;
import java.io.IOException;
import java.util.HashMap;
import java.util.Locale;
import javax.naming.NamingException;
import javax.naming.InitialContext;
import com.sun.j2ee.blueprints.petstore.util.JNDINames;import com.sun.j2ee.blueprints.petstore.control.exceptions.SigninFailedException;
import com.sun.j2ee.blueprints.petstore.control.exceptions.GeneralFailureException;
import com.sun.j2ee.blueprints.util.tracer.Debug;
import com.sun.j2ee.blueprints.petstore.control.web.ModelManager;
import com.sun.j2ee.blueprints.petstore.control.web.CustomerWebImpl;
import com.sun.j2ee.blueprints.petstore.control.web.ScreenFlowXmlDAO;
import com.sun.j2ee.blueprints.petstore.control.web.RequestProcessor;
import com.sun.j2ee.blueprints.petstore.util.WebKeys;
import com.sun.j2ee.blueprints.petstore.util.JSPUtil;public class MainServlet extends HttpServlet {    private HashMap urlMappings;    public void init() {
        Debug.println("MainServlet: Initializing");
        String requestMappingsURL = null;
        try {
            requestMappingsURL = getServletContext().getResource("/WEB-INF/xml/requestmappings.xml").toString();
        } catch (java.net.MalformedURLException ex) {
            Debug.println("ScreenFlowManager: initializing ScreenFlowManager malformed URL exception: " + ex);
        }
       urlMappings = ScreenFlowXmlDAO.loadRequestMappings(requestMappingsURL);
       getServletContext().setAttribute(WebKeys.URLMappingsKey, urlMappings);
       Debug.println("MainServlet: loaded urlMappings");
       String serverType = null;
       try {
            InitialContext ic = new InitialContext();
            serverType = (String)ic.lookup(JNDINames.SERVER_TYPE);
            getServletContext().setAttribute(WebKeys.ServerTypeKey, serverType);
        } catch (NamingException ex) {
            Debug.println("Server Type not specified in deployment descriptor: using default J2ee Security Adapter");
        }
        getScreenFlowManager();
        getRequestProcessor();
        Debug.println("MainServlet: Initialization complete");
    }     public  void doPost(HttpServletRequest request, HttpServletResponse  response)
        throws IOException, ServletException {
        doGet(request, response);
    }    public  void doGet(HttpServletRequest request, HttpServletResponse  response)
        throws IOException, ServletException {
        String selectedURL = request.getPathInfo();
        // the current tomcat is resetting the outputstream so this is a workaround
        if ((selectedURL != null) && selectedURL.equals("/white")) return;
        HttpSession session = request.getSession();
        ScreenFlowManager screenManager = null;
        ModelManager modelManager= (ModelManager)request.getSession().getAttribute(WebKeys.ModelManagerKey);
        if ( modelManager == null ) {
            try {
                        modelManager = (ModelManager) Beans.instantiate(this.getClass().getClassLoader(), "com.sun.j2ee.blueprints.petstore.control.web.ModelManager");
             } catch (Exception exc) {
                 throw new ServletException ("Cannot create bean of class ModelManager");
             }
             session.setAttribute(WebKeys.ModelManagerKey, modelManager);
             modelManager.init(getServletContext(), session);
         }
         Debug.println("MainServlet: url " + selectedURL);
         // check if url is protected before processing request
         URLMapping current = getURLMapping(selectedURL);
         if ((current != null) && current.requiresSignin()) {
             CustomerWebImpl customer = modelManager.getCustomerWebImpl();
             if (customer.isLoggedIn()) {
                 doProcess(request);
             } else {
                 String signinScreen = getScreenFlowManager().getSigninScreen();
                 session.setAttribute(WebKeys.CurrentScreen, signinScreen);
                 session.setAttribute(WebKeys.SigninTargetURL, selectedURL);
             }
         } else {
             doProcess(request);
         }
            /**
                Default to the base language or the site.
             If a language is found in the session use that template.
             */
             Locale locale = JSPUtil.getLocale(request.getSession());
             getServletConfig().getServletContext().getRequestDispatcher(getScreenFlowManager().getTemplate(locale)).forward(request, response);    }    private void doProcess(HttpServletRequest request) throws ServletException {
        try {
                 getRequestProcessor().processRequest(request);
                 getScreenFlowManager().getNextScreen(request);
        } catch (Throwable ex) {
            String className = ex.getClass().getName();
            String exceptionScreen = getScreenFlowManager().getExceptionScreen(className);
            Debug.println("MainServlet: target screen is: " + exceptionScreen);
            // put the exception in the request
            request.setAttribute("javax.servlet.jsp.jspException", ex);
            if (exceptionScreen != null) {
                request.getSession().setAttribute(WebKeys.CurrentScreen, exceptionScreen);
            } else {
                // send to general error screen
                Debug.println("MainServlet: unknown exception: " + className);
                throw new ServletException("MainServlet: unknown exception: " + className);
           }
       }
    }    private RequestProcessor getRequestProcessor() {
         RequestProcessor rp = (RequestProcessor)getServletContext().getAttribute(WebKeys.RequestProcessorKey);
         if ( rp == null ) {
             Debug.println("MainServlet: initializing request processor");
             rp = new RequestProcessor();
             rp.init(getServletContext());
             getServletContext().setAttribute(WebKeys.RequestProcessorKey, rp);
        }
       return rp;
    }    private ScreenFlowManager getScreenFlowManager() {
            ScreenFlowManager screenManager = (ScreenFlowManager)getServletContext().getAttribute(WebKeys.ScreenManagerKey);
            if (screenManager == null ) {
                Debug.println("MainServlet: Loading screen flow definitions");
                screenManager = new ScreenFlowManager();
                screenManager.init(getServletContext());
                getServletContext().setAttribute(WebKeys.ScreenManagerKey, screenManager);
             }
        return screenManager;
    }    /**
     * The UrlMapping object contains information that will match
     * a url to a mapping object that contains information about
     * the current screen, the RequestHandler that is needed to
     * process a request, and the RequestHandler that is needed
     * to insure that the propper screen is displayed.
    */    private URLMapping getURLMapping(String urlPattern) {
        if ((urlMappings != null) && urlMappings.containsKey(urlPattern)) {
            return (URLMapping)urlMappings.get(urlPattern);
        } else {
            return null;
        }
    }}

Answer 15

init（） 方法是web容器 启动的的时候就解析的～～
requestMappingsURL = getServletContext().getResource("/WEB-INF/xml/requestmappings.xml").toString();将XML解析成一个字符串 具体怎么排列的你调试下就知道了 我没安装环境。
urlMappings = ScreenFlowXmlDAO.loadRequestMappings(requestMappingsURL); 
ScreenFlowXmlDAO 这个类是这个工程的类 我想应该是吧 这个字符串解析成一个key对应一个alue的 hashmap 大约就是 signin SIGN_IN_SUCCESS 的样子 然后将这个hashmap 保存 getServletContext().setAttribute(WebKeys.URLMappingsKey, urlMappings);然后在页面点击连接的时候进行doget和dopost请求都进入 doGet（requet，response）方法 String selectedURL = request.getPathInfo(); 获得uri 然后经过处理 比较modelManager = (ModelManager) Beans.instantiate(this.getClass().getClassLoader(), "com.sun.j2ee.blueprints.petstore.control.web.ModelManager"); 这个就是转向的代码你这个是的deamo 你可以调试一下 一步一步的跟下就很清楚了  其中中间 还经过了很多的处理 有点复杂 我不调试也说不清