自定义mvc框架（2）

最新推荐文章于 2023-06-29 21:43:07 发布

原创最新推荐文章于 2023-06-29 21:43:07 发布 · 122 阅读

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1. 什么是MVC

MVC全名是Model View Controller，是模型(model)－视图(view)－控制器(controller)的缩写，
它是一种软件设计典范，用一种业务逻辑、数据、界面显示分离的方法组织代码。
核心思想：各司其职

2. MVC结构

V
jsp/ios/android
C
servlet/action
M
实体域模型(名词)
过程域模型(动词)
注1：不能跨层调用
注2：只能出现由上而下的调用

3. 自定义MVC工作原理图

在这里插入图片描述

4.自定义mvc解决的问题

在这里插入图片描述

5. 通过XML对自定义mvc框架进行增强

导入jar包
创建4个工具类
（1）、ActionModel：

package com.cjq.framework;
import java.io.Serializable;
import java.util.HashMap;
import java.util.Map;
/**
*用来描述action标签 
 *
 */
public class ActionModel implements Serializable{ private static final long serialVersionUID = 6145949994701469663L;
 
 private Map<String, ForwardModel> forwardModels = new HashMap<String, ForwardModel>();
 
 private String path;
 
 private String type;
 
 public String getPath() {
  return path;
 } public void setPath(String path) {
  this.path = path;
 } public String getType() {
  return type;
 } public void setType(String type) {
  this.type = type;
 } public void put(ForwardModel forwardModel){
  forwardModels.put(forwardModel.getName(), forwardModel);
 }
 
 public ForwardModel get(String name){
  return forwardModels.get(name);
 }
 
}

（2）、ConfigModel ：

package com.cjq.framework;
import java.io.Serializable;
import java.util.HashMap;
import java.util.Map;/**
 *用来描述config标签
 * @author cjq
 *
 */
public class ConfigModel implements Serializable{ private static final long serialVersionUID = 225631995869970136L;
 private Map<String, ActionModel> actionModels = new HashMap<String, ActionModel>();
 
 public void put(ActionModel actionModel){
  actionModels.put(actionModel.getPath(), actionModel);
 }
 
 public ActionModel get(String name){
  return actionModels.get(name);
 }
 
}

（3）、ConfigModelFactory：

package com.cjq.framework;
import java.io.InputStream;
import java.util.List;import org.dom4j.Document;
import org.dom4j.Element;
import org.dom4j.io.SAXReader;public class ConfigModelFactory {
 private ConfigModelFactory() { } private static ConfigModel configModel = null; public static ConfigModel newInstance() throws Exception {
  return newInstance("mvc.xml");
 } /**
  *工厂模式创建config建模对象
  * 
  * @param path
  * @return
  * @throws Exception
  */
 public static ConfigModel newInstance(String path) throws Exception {
  if (null != configModel) {
   return configModel;
  }  ConfigModel configModel = new ConfigModel();
  InputStream is = ConfigModelFactory.class.getResourceAsStream(path);
  SAXReader saxReader = new SAXReader();
  Document doc = saxReader.read(is);
  List<Element> actionEleList = doc.selectNodes("/config/action");
  ActionModel actionModel = null;
  ForwardModel forwardModel = null;
  for (Element actionEle : actionEleList) {
    actionModel = new ActionModel();
   actionModel.setPath(actionEle.attributeValue("path"));
   actionModel.setType(actionEle.attributeValue("type"));
   List<Element> forwordEleList = actionEle.selectNodes("forward");
   for (Element forwordEle : forwordEleList) {
    forwardModel = new ForwardModel();
    forwardModel.setName(forwordEle.attributeValue("name"));
    forwardModel.setPath(forwordEle.attributeValue("path"));
    forwardModel.setRedirect(forwordEle.attributeValue("redirect"));
    actionModel.put(forwardModel);
   }   configModel.put(actionModel);
  }  return configModel;
 }
 
 public static void main(String[] args) {
  try {
   ConfigModel configModel = ConfigModelFactory.newInstance();
   ActionModel actionModel = configModel.get("/loginAction");
   ForwardModel forwardModel = actionModel.get("failed");
   System.out.println(actionModel.getType());
   System.out.println(forwardModel.getPath());
  } catch (Exception e) {
   e.printStackTrace();
  }
 }
}

（4）、ForwardModel

package com.cjq.framework;
import java.io.Serializable;/**
 * 用来描述forward标签
 * @author cjq
 *  */
public class ForwardModel implements Serializable { 
 private static final long serialVersionUID = -8449173017919821212L;
 
 private String name;
 private String path;
 private String redirect; public String getName() {
  return name;
 } public void setName(String name) {
  this.name = name;
 } public String getPath() {
  return path;
 } public void setPath(String path) {
  this.path = path;
 } public String getRedirect() {
  return redirect;
 } public void setRedirect(String redirect) {
  this.redirect = redirect;
 }}

案例一：对存放控制器action容器的增强

DispatcherServlet 中央控制器

package com.cjq.framework;
import java.io.IOException;
import java.lang.reflect.InvocationTargetException;import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;import org.apache.commons.beanutils.BeanUtils;import com.cjq.web.AddCalAction;
import com.cjq.web.DelCalAction;
import com.cjq.web.ChengCalAction;
import com.cjq.web.ChuCalAction;/**
 * 中央控制器 作用： 接受用户器请求，通过用户请求的url寻找指定的子控制器去处理业务
 *
 * 增强actionMap： 1.对存放子控制器增强action容器的增强 为什么要做？：原来为了完成业务需求，需要不断修改框架的代码，这样设计是不合理的
 * 处理方法：参照web.xml的设计方法，来完成中央控制器管理子控制器的动态配置
 *
 * 2.处理结果的跳转形式 达到简化代码的目的
 *
 * 3.将一组操作放到一个子控制器去完成
 *
 * 4.处理jsp传递到后台的参数封装
 *
 * 5.解决框架配置文件重名冲突问题
 *
 */
public class DispatcherServlet extends HttpServlet{ private static final long serialVersionUID = 1L;
 private ConfigModel configModel=null;
 public void init() {
  try {
   configModel=ConfigModelFactory.newInstance();
  } catch (Exception e) {
   e.printStackTrace();
  }
 }
 
 @Override
 protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
  doPost(req, resp);
 }
 
 @Override
 protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
  String url=req.getRequestURI();
  url=url.substring(url.lastIndexOf("/"), url.lastIndexOf("."));
  ActionModel actionModel = configModel.get(url);
  try {
   Action action = (Action) Class.forName(actionModel.getType()).newInstance();
   action.execute(req, resp);
  } catch (InstantiationException | IllegalAccessException | ClassNotFoundException e) {
   e.printStackTrace();
     }
 }
}

mvc.xml配置文件

<?xml version="1.0" encoding="UTF-8"?>
<config>
 <action path="/cal_add" type="com.cjq.web.AddCalAction">
  <forward name="rs" path="/rs.jsp" redirect="false" />
 </action>
 <action path="/cal_del" type="com.cjq.web.DelCalAction">
  <forward name="rs" path="/rs.jsp" redirect="false" />
 </action>
 <action path="/cal_cheng" type="com.cjq.web.ChengCalAction">
  <forward name="rs" path="/rs.jsp" redirect="false" />
 </action>
 <action path="/cal_chu" type="com.cjq.web.ChuCalAction">
  <forward name="rs" path="/rs.jsp" redirect="false" />
 </action>
</config>

运行结果（加）：
在这里插入图片描述
结果为：6

案例二：处理结果码的跳转形式

修改AddCalAction

package com.cjq.web;
import java.io.IOException;import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;import com.cjq.framework.Action;import com.cjq.entity.Cal;/**
 * 实现子控制器 
 * AddCalAction加法 
 * 处理计算机加法业务类
 */
public class AddCalAction implements Action { @Override
 public String execute(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
  String num1 = req.getParameter("num1");// 实体类
  String num2 = req.getParameter("num2");
  Cal cal = new Cal(num1, num2);
  req.setAttribute("rs", Integer.valueOf(cal.getNum1()) + Integer.valueOf(cal.getNum2()));
  req.getRequestDispatcher("/rs.jsp").forward(req, resp);
  return "rs";
 }}

DispatcherServlet 中央控制器

package com.cjq.framework;
import java.io.IOException;
import java.lang.reflect.InvocationTargetException;import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;import org.apache.commons.beanutils.BeanUtils;import com.cjq.web.AddCalAction;
import com.cjq.web.DelCalAction;
import com.cjq.web.ChengCalAction;
import com.cjq.web.ChuCalAction;/**
 * 中央控制器 作用： 接受用户器请求，通过用户请求的url寻找指定的子控制器去处理业务
 *
 * 增强actionMap： 1.对存放子控制器增强action容器的增强 为什么要做？：原来为了完成业务需求，需要不断修改框架的代码，这样设计是不合理的
 * 处理方法：参照web.xml的设计方法，来完成中央控制器管理子控制器的动态配置
 *
 * 2.处理结果的跳转形式 达到简化代码的目的
 *
 * 3.将一组操作放到一个子控制器去完成
 *
 * 4.处理jsp传递到后台的参数封装
 *
 * 5.解决框架配置文件重名冲突问题
 *
 */
public class DispatcherServlet extends HttpServlet{ private static final long serialVersionUID = 1L;
 private ConfigModel configModel=null;
 public void init() {
  try {
   configModel=ConfigModelFactory.newInstance();
  } catch (Exception e) {
   e.printStackTrace();
  }
 }
 
 @Override
 protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
  doPost(req, resp);
 }
 
 @Override
 protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
  String url=req.getRequestURI();
  url=url.substring(url.lastIndexOf("/"), url.lastIndexOf("."));
  ActionModel actionModel = configModel.get(url);
  try {
   if(actionModel==null) {
    throw new RuntimeException("您没有配置指定的子控制器来处理用户请求");
   }
   Action action = (Action) Class.forName(actionModel.getType()).newInstance();
   String code=action.execute(req, resp);
   ForwardModel forwardModel=actionModel.get(code);
   if("false".equals(forwardModel.getRedirect())) {
    req.getRequestDispatcher(forwardModel.getPath()).forward(req, resp);
   }else {
    //注意：默认会损坏项目名
    //resp.sendRedirect(forwardModel.getPath());
    resp.sendRedirect(req.getContextPath()+forwardModel.getPath());
   }
  } catch (InstantiationException | IllegalAccessException | ClassNotFoundException e) {
   e.printStackTrace();
     }
 }
}

mvc.xml文件：

<?xml version="1.0" encoding="UTF-8"?>
<config>
 <action path="/cal_add" type="com.cjq.web.AddCalAction">
  <forward name="rs" path="/rs.jsp" redirect="false" />
 </action>
 <action path="/cal_del" type="com.cjq.web.DelCalAction">
  <forward name="rs" path="/rs.jsp" redirect="false" />
 </action>
 <!-- <action path="/cal_cheng" type="com.cjq.web.ChengCalAction">
  <forward name="rs" path="/rs.jsp" redirect="false" />
 </action> -->
 <action path="/cal_chu" type="com.cjq.web.ChuCalAction">
  <forward name="rs" path="/rs.jsp" redirect="false" />
 </action>
</config>

运行结果：
在这里插入图片描述

案例三：将一组操作一个子控制器去完成

ActionSupport 增强版的子控制器：

package com.cjq.framework;
import java.io.IOException;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;/**
 * 3.增强版的子控制器 
 *   作用： 将一组操作放到一个子控制器去完成
 */
public class ActionSupport implements Action { @Override
 public String execute(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
  // 从前台传递需要调用的方法名到后台，实现动态方法调用
  // 要用到反射
  String methodName = req.getParameter("methodName");// methodName把参数传到jsp页面
  String code = null;
  try {
   Method m = this.getClass().getDeclaredMethod(methodName, HttpServletRequest.class,
     HttpServletResponse.class);
   m.setAccessible(true);// 打开访问权限
   code = (String) m.invoke(this, req, resp);// 执行方法传返回值  } catch (NoSuchMethodException | SecurityException e) {
   e.printStackTrace();
  } catch (IllegalAccessException e) {
   e.printStackTrace();
  } catch (IllegalArgumentException e) {
   e.printStackTrace();
  } catch (InvocationTargetException e) {
   e.printStackTrace();
  }
  return code;
 }}

CalAction：

package com.cjq.web;
import java.io.IOException;import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;import com.cjq.framework.ActionSupport;
import com.cjq.framework.ModelDriven;import com.cjq.entity.Cal;public class CalAction extends ActionSupport{
 public String add(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
  String num1=req.getParameter("num1");
  String num2=req.getParameter("num2");
  Cal cal=new Cal(num1, num2);
  req.setAttribute("rs", Integer.valueOf(cal.getNum1())+Integer.valueOf(cal.getNum2()));
  return "rs";
 }
 
 public String del(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
  String num1=req.getParameter("num1");
  String num2=req.getParameter("num2");
  Cal cal=new Cal(num1, num2);
  req.setAttribute("rs", Integer.valueOf(cal.getNum1())-Integer.valueOf(cal.getNum2()));
  return "rs";
 }
public String cheng(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
  String num1=req.getParameter("num1");
  String num2=req.getParameter("num2");
  Cal cal=new Cal(num1, num2);
  req.setAttribute("rs", Integer.valueOf(cal.getNum1())*Integer.valueOf(cal.getNum2()));
  return "rs";
 }
 
 public String chu(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
  String num1=req.getParameter("num1");
  String num2=req.getParameter("num2");
  Cal cal=new Cal(num1, num2);
  req.setAttribute("rs", Integer.valueOf(cal.getNum1())/Integer.valueOf(cal.getNum2()));
  return "rs";
 }
}

mvc.xml文件：

<?xml version="1.0" encoding="UTF-8"?>
<config>
 <action path="/cal" type="com.xwt.framework.CalAction">
  <forward name="rs" path="/rs.jsp" redirect="false" />
 </action>
</config>

cal.jsp：

<%@ page language="java" contentType="text/html; charset=utf-8"
    pageEncoding="utf-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>mvc</title>
<script type="text/javascript">
function doSub(v) {
 if(v==1){
        calForm.action="${pageContext.request.contextPath}/cal.action?methodName=add";
 }else if(v==2){
     calForm.action="${pageContext.request.contextPath}/cal.action?methodName=del";
 }else if(v==3){
     calForm.action="${pageContext.request.contextPath}/cal.action?methodName=cheng";
 }else if(v==4){
     calForm.action="${pageContext.request.contextPath}/cal.action?methodName=chu";
 }
     calForm.submit;//提交
}
</script></head>
<body><form id="calForm" method="post">
    num1:<input type="text"name="num1"><br>
    num2:<input type="text"name="num2"><br>  
    <button onclick="doSub(1)">+</button>
    <button onclick="doSub(2)">-</button>
    <button onclick="doSub(3)">*</button>
    <button onclick="doSub(4)">/</button>
</form></body>
</html>

案例四：处理jsp传递到后台的参数封装

ModelDriven接口：

package com.cjq.framework;
/**
 *模型驱动接口
 *作用：
 *给对应处理业务的子控制器中包含的实体类进行jsp参数封装
 * @param <T>驱动所有类，为泛型
 */
public interface ModelDriven<T> {
 T getModel();
}

CalAction ：

package com.cjq.web;
import java.io.IOException;import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;import com.cjq.framework.ActionSupport;
import com.cjq.framework.ModelDriven;import com.cjq.entity.Cal;public class CalAction extends ActionSupport implements ModelDriven<Cal>{
 
 private Cal cal=new Cal();
 
 public String add(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
  req.setAttribute("rs", Integer.valueOf(cal.getNum1())+Integer.valueOf(cal.getNum2()));
  return "rs";
 }
 
 public String del(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
  return "rs";
 }
 
 public String cheng(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
  req.setAttribute("rs", Integer.valueOf(cal.getNum1())*Integer.valueOf(cal.getNum2()));
  return "rs";
 }
 
 public String chu(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
  req.setAttribute("rs", Integer.valueOf(cal.getNum1())/Integer.valueOf(cal.getNum2()));
  return "rs";
 } @Override
 public Cal getModel() {
  return cal;
 }
}

更改中央控制器 DispatcherServlet

package com.cjq.framework;
import java.io.IOException;
import java.lang.reflect.InvocationTargetException;import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;import org.apache.commons.beanutils.BeanUtils;import com.cjq.web.AddCalAction;
import com.cjq.web.DelCalAction;
import com.cjq.web.ChengCalAction;
import com.cjq.web.ChuCalAction;/**
 * 中央控制器 作用： 接受用户器请求，通过用户请求的url寻找指定的子控制器去处理业务
 *
 * 增强actionMap： 1.对存放子控制器增强action容器的增强 为什么要做？：原来为了完成业务需求，需要不断修改框架的代码，这样设计是不合理的
 * 处理方法：参照web.xml的设计方法，来完成中央控制器管理子控制器的动态配置
 *
 * 2.处理结果的跳转形式 达到简化代码的目的
 *
 * 3.将一组操作放到一个子控制器去完成
 *
 * 4.处理jsp传递到后台的参数封装
 *
 * 5.解决框架配置文件重名冲突问题
 *
 */
public class DispatcherServlet extends HttpServlet { private static final long serialVersionUID = 1L;
 private ConfigModel configModel = null; public void init() {
  try {
   configModel = ConfigModelFactory.newInstance();
  } catch (Exception e) {
   e.printStackTrace();
  }
 } @Override
 protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
  doPost(req, resp);
 } @Override
 protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
  String url = req.getRequestURI();
  url = url.substring(url.lastIndexOf("/"), url.lastIndexOf("."));
  ActionModel actionModel = configModel.get(url);
  try {
   if (actionModel == null) {
    throw new RuntimeException("您没有配置指定的子控制器来处理用户请求");
   }
   Action action = (Action) Class.forName(actionModel.getType()).newInstance();
   if (action instanceof ModelDriven) {
    ModelDriven modelDriven = (ModelDriven) action;
    Object model = modelDriven.getModel();
    // 给model赋值了，意味着在调用add/del方法的时候cal不再是空的了
    // req.getParameterMap();//封装了所有前台的键值对
    BeanUtils.populate(model, req.getParameterMap());
   }   String code = action.execute(req, resp);
   ForwardModel forwardModel = actionModel.get(code);
   if ("false".equals(forwardModel.getRedirect())) {
    req.getRequestDispatcher(forwardModel.getPath()).forward(req, resp);
   } else {
    // 注意：默认会损坏项目名
    resp.sendRedirect(req.getContextPath() + forwardModel.getPath());
   }
  } catch (InstantiationException | IllegalAccessException | ClassNotFoundException
    | InvocationTargetException e) {
   e.printStackTrace();
  }
 }}

案例五：解决框架配置文件重名冲突问题

更改中央控制器 DispatcherServlet

package com.cjq.framework;
import java.io.IOException;
import java.lang.reflect.InvocationTargetException;import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;import org.apache.commons.beanutils.BeanUtils;import com.cjq.web.AddCalAction;
import com.cjq.web.DelCalAction;
import com.cjq.web.ChengCalAction;
import com.cjq.web.ChuCalAction;/**
 * 中央控制器 作用： 接受用户器请求，通过用户请求的url寻找指定的子控制器去处理业务
 *
 * 增强actionMap： 1.对存放子控制器增强action容器的增强 为什么要做？：原来为了完成业务需求，需要不断修改框架的代码，这样设计是不合理的
 * 处理方法：参照web.xml的设计方法，来完成中央控制器管理子控制器的动态配置
 *
 * 2.处理结果的跳转形式 达到简化代码的目的
 *
 * 3.将一组操作放到一个子控制器去完成
 *
 * 4.处理jsp传递到后台的参数封装
 *
 * 5.解决框架配置文件重名冲突问题
 *
 */
public class DispatcherServlet extends HttpServlet { private static final long serialVersionUID = 1L;
 private ConfigModel configModel = null; public void init() {
  try {
   String mvcXmlLocation = this.getInitParameter("mvcXmlLocation");
   if (null == mvcXmlLocation || "".equals(mvcXmlLocation)) {
    mvcXmlLocation = "mvc.xml";
   }
   System.out.println("mvcXmlLocation:" + mvcXmlLocation);
   configModel = ConfigModelFactory.newInstance();
  } catch (Exception e) {
   e.printStackTrace();
  }
 } @Override
 protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
  doPost(req, resp);
 } @Override
 protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
  String url = req.getRequestURI();
  url = url.substring(url.lastIndexOf("/"), url.lastIndexOf("."));
  ActionModel actionModel = configModel.get(url);
  try {
   if (actionModel == null) {
    throw new RuntimeException("您没有配置指定的子控制器来处理用户请求");
   }
   Action action = (Action) Class.forName(actionModel.getType()).newInstance();
   if (action instanceof ModelDriven) {
    ModelDriven modelDriven = (ModelDriven) action;
    Object model = modelDriven.getModel();
    // 给model赋值了，意味着在调用add/del方法的时候cal不再是空的了
    // req.getParameterMap();//封装了所有前台的键值对
    BeanUtils.populate(model, req.getParameterMap());
   }   String code = action.execute(req, resp);
   ForwardModel forwardModel = actionModel.get(code);
   if ("false".equals(forwardModel.getRedirect())) {
    req.getRequestDispatcher(forwardModel.getPath()).forward(req, resp);
   } else {
    // 注意：默认会损坏项目名
    resp.sendRedirect(req.getContextPath() + forwardModel.getPath());
   }
  } catch (InstantiationException | IllegalAccessException | ClassNotFoundException
    | InvocationTargetException e) {
   e.printStackTrace();
  }
 }}

运行结果如下：
在这里插入图片描述
配置yo.xml文件：

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://xmlns.jcp.org/xml/ns/javaee" xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd" id="WebApp_ID" version="3.1">
  <display-name>cjq_mvc</display-name>
  <servlet>
     <servlet-name>dispatcherServlet</servlet-name>
     <servlet-class>com.cjq.framework.DispatcherServlet</servlet-class>
     <init-param>
     <param-name>mvcXmlLocation</param-name>
     <param-value>/yo.xml</param-value>
     </init-param>
  </servlet>
  <servlet-mapping>
     <servlet-name>dispatcherServlet</servlet-name>
     <url-pattern>*.action</url-pattern>
  </servlet-mapping>
</web-app>

运行结果如下：
在这里插入图片描述