本文共 27403 字，大约阅读时间需要 91 分钟。

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

自定义MVC工作原理图

主控制动态调用子控制器调用完成具体的业务逻辑 请求、主控制器、子控制器 例子：计算机两个数的加减乘除 Entity封装

package com.zxp.entity;public class Cal {private String url;//地址private String num1;private String num2;public String getUrl() {	return url;}public void setUrl(String url) {	this.url = url;}public String getNum1() {	return num1;}public void setNum1(String num1) {	this.num1 = num1;}public String getNum2() {	return num2;}public void setNum2(String num2) {	this.num2 = num2;}public Cal( String num1, String num2) {	super();	this.num1 = num1;	this.num2 = num2;}public Cal() {	super();}}

framework子控制器

package com.zxp.framework;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;/** * 子控制器 * 作用： * 具体处理用户请求的类（实现Action接口的类） * @author 玉姬 * */public interface Action {	String execute(HttpServletRequest req, HttpServletResponse resp) ;}

Web请求

加

package com.zxp.web;import java.io.IOException;import javax.servlet.ServletException;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import com.sun.net.httpserver.spi.HttpServerProvider;import com.zxp.entity.Cal;import com.zxp.framework.Action;public class AddCallAction implements Action {	//处理请求	@Override	public String execute(HttpServletRequest req, HttpServletResponse resp)  {		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()));		try {			req.getRequestDispatcher("/rs.jsp").forward(req, resp);		} catch (ServletException | IOException e) {			// TODO Auto-generated catch block			e.printStackTrace();		}		return null;	}	}

减

package com.zxp.web;import java.io.IOException;import javax.servlet.ServletException;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import com.sun.net.httpserver.spi.HttpServerProvider;import com.zxp.entity.Cal;-import com.zxp.framework.Action;public class DelCallAction implements Action {	//处理请求	@Override	public String execute(HttpServletRequest req, HttpServletResponse resp)  {		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()));		try {			req.getRequestDispatcher("/rs.jsp").forward(req, resp);		} catch (ServletException | IOException e) {			// TODO Auto-generated catch block			e.printStackTrace();		}		return null;	}	}

乘

package com.zxp.web;import java.io.IOException;import javax.servlet.ServletException;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import com.sun.net.httpserver.spi.HttpServerProvider;import com.zxp.entity.Cal;import com.zxp.framework.Action;public class MulCallAction implements Action {	//处理请求	@Override	public String execute(HttpServletRequest req, HttpServletResponse resp)  {		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()));		try {			req.getRequestDispatcher("/rs.jsp").forward(req, resp);		} catch (ServletException | IOException e) {			// TODO Auto-generated catch block			e.printStackTrace();		}		return null;	}	}

除

package com.zxp.web;import java.io.IOException;import javax.servlet.ServletException;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import com.sun.net.httpserver.spi.HttpServerProvider;import com.zxp.entity.Cal;import com.zxp.framework.Action;public class DivCallAction implements Action {	//处理请求	@Override	public String execute(HttpServletRequest req, HttpServletResponse resp)  {		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()));		try {			req.getRequestDispatcher("/rs.jsp").forward(req, resp);		} catch (ServletException | IOException e) {			// TODO Auto-generated catch block			e.printStackTrace();		}		return null;	}	}

framework中央控制器

package com.zxp.framework;import java.io.IOException;import java.util.HashMap;import java.util.Map;import javax.servlet.ServletException;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import com.zxp.web.AddCallAction;import com.zxp.web.DelCallAction;import com.zxp.web.DivCallAction;import com.zxp.web.MulCallAction;/** * 中央控制器 * 作用： * 接受用户请求，通过用户请求的url寻求指定的子控制器去处理业务 * @author 玉姬 * */public class DispatcherServlet extends HttpServlet {	private static final long serialVersionUID = -2291078179694007198L;//	容器存放	private Map
   
     actionMap=new HashMap
    
     ();	//	url和uri的区别 地址区别//	url  :http://localhost:8080/T_mvc/cal.add.action//  uri  :T_mvc/cal.add.action		public void init() {//		初始化   		actionMap.put("/cal_add", new AddCallAction());//发出请求		actionMap.put("/cal_del", new DelCallAction());//发出请求		actionMap.put("/cal_mul", new MulCallAction());		actionMap.put("/cal_div", new DivCallAction());	}	@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("."));//		AddCallAction action=(AddCallAction) actionMap.get(url);//		Action a=action;		Action action=actionMap.get(url);		action.execute(req, resp);		}	}
    
   

配置

   
     
    
     T_mvc
      
        
     
      cal.jsp
       
      
      
     
      dispatcherServlet
       
     
      com.zxp.framework.DispatcherServlet
       
      
      
     
      dispatcherServlet
       
     
      *.action
       
      
   

Jsp页面

主页面

<%@ page language="java" contentType="text/html; charset=utf-8"    pageEncoding="utf-8"%>
   
   
    num1:
    
    
num2:
    
    
    +
    -
    *
    /
   

结果页面

<%@ page language="java" contentType="text/html; charset=utf-8"    pageEncoding="utf-8"%>
   结果：${rs }

运行

加 减 乘 除

自定义MVC框架五步增强

1、 Action的动态配置

为什么：为了完成业务需求需要不断修改框架代码。这样设计是不合理的 处理：参照web.xml的实际方法，来完成中央控制管理子控制器的动态配置

package com.zxp.framework;import java.io.IOException;import java.util.HashMap;import java.util.Map;import javax.servlet.ServletException;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import com.zxp.web.AddCallAction;import com.zxp.web.DelCallAction;import com.zxp.web.DivCallAction;import com.zxp.web.MulCallAction;/** * 中央控制器 * 作用： * 接受用户请求，通过用户请求的url寻求指定的子控制器去处理业务 *  *  * 1.对存放子控制器action容器的增强 * 为什么：为了完成业务需求需要不断修改框架代码。这样设计是不合理的 * 处理：参照web.xml的实际方法，来完成中央控制管理子控制器的动态配置 * @author 玉姬 * */public class DispatcherServlet extends HttpServlet {	private static final long serialVersionUID = -2291078179694007198L;//	容器存放//	private Map
   
     actionMap=new HashMap
    
     ();	private ConfigModel configModel=null;//	url和uri的区别 地址区别//	url  :http://localhost:8080/T_mvc/cal.add.action//  uri  :T_mvc/cal.add.action		public void init() {//		初始化   //		actionMap.put("/cal_add", new AddCallAction());//发出请求//		actionMap.put("/cal_del", new DelCallAction());//发出请求//		actionMap.put("/cal_mul", new MulCallAction());//		actionMap.put("/cal_div", new DivCallAction());		try {			configModel=ConfigModelFactory.newInstance();		} catch (Exception e) {			// TODO Auto-generated catch block			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("."));//		AddCallAction action=(AddCallAction) actionMap.get(url);//		Action a=action;//		Action action=actionMap.get(url);//		action.execute(req, resp);		ActionModel actionModel=configModel.get(url);		try {			Action action=(Action) getClass().forName(actionModel.getType()).newInstance();			action.execute(req, resp);		} catch (InstantiationException e) {			// TODO Auto-generated catch block			e.printStackTrace();		} catch (IllegalAccessException e) {			// TODO Auto-generated catch block			e.printStackTrace();		} catch (ClassNotFoundException e) {			// TODO Auto-generated catch block			e.printStackTrace();		}		}	}
    
   

配置

运行加法

2、 子控制器返回码的处理 处理结果码的调转形式 达到简化代码的结果 加

package com.zxp.web;import java.io.IOException;import javax.servlet.ServletException;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import com.sun.net.httpserver.spi.HttpServerProvider;import com.zxp.entity.Cal;import com.zxp.framework.Action;public class AddCallAction implements Action {	//处理请求	@Override	public String execute(HttpServletRequest req, HttpServletResponse resp)  {		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()));//		try {//			req.getRequestDispatcher("/rs.jsp").forward(req, resp);//		} catch (ServletException | IOException e) {//			// TODO Auto-generated catch block//			e.printStackTrace();//		}		return "rs";	}	}

减

package com.zxp.web;import java.io.IOException;import javax.servlet.ServletException;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import com.sun.net.httpserver.spi.HttpServerProvider;import com.zxp.entity.Cal;import com.zxp.framework.Action;public class DelCallAction implements Action {	//处理请求	@Override	public String execute(HttpServletRequest req, HttpServletResponse resp)  {		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()));//		try {//			req.getRequestDispatcher("/rs.jsp").forward(req, resp);//		} catch (ServletException | IOException e) {//			// TODO Auto-generated catch block//			e.printStackTrace();//		}		return "rs";	}	}

乘

package com.zxp.web;import java.io.IOException;import javax.servlet.ServletException;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import com.sun.net.httpserver.spi.HttpServerProvider;import com.zxp.entity.Cal;import com.zxp.framework.Action;public class MulCallAction implements Action {	//处理请求	@Override	public String execute(HttpServletRequest req, HttpServletResponse resp)  {		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()));//		try {//			req.getRequestDispatcher("/rs.jsp").forward(req, resp);//		} catch (ServletException | IOException e) {//			// TODO Auto-generated catch block//			e.printStackTrace();//		}		return "rs";	}	}

除

package com.zxp.web;import java.io.IOException;import javax.servlet.ServletException;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import com.sun.net.httpserver.spi.HttpServerProvider;import com.zxp.entity.Cal;import com.zxp.framework.Action;public class DivCallAction implements Action {	//处理请求	@Override	public String execute(HttpServletRequest req, HttpServletResponse resp)  {		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()));//		try {//			req.getRequestDispatcher("/rs.jsp").forward(req, resp);//		} catch (ServletException | IOException e) {//			// TODO Auto-generated catch block//			e.printStackTrace();//		}		return "rs";	}	}

中央控制器

package com.zxp.framework;import java.io.IOException;import java.util.HashMap;import java.util.Map;import javax.management.RuntimeErrorException;import javax.servlet.ServletException;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import com.zxp.web.AddCallAction;import com.zxp.web.DelCallAction;import com.zxp.web.DivCallAction;import com.zxp.web.MulCallAction;/** * 中央控制器 * 作用： * 接受用户请求，通过用户请求的url寻求指定的子控制器去处理业务 *  *  * 1.对存放子控制器action容器的增强 * 为什么：为了完成业务需求需要不断修改框架代码。这样设计是不合理的 * 处理：参照web.xml的实际方法，来完成中央控制管理子控制器的动态配置 *  * 2。处理结果码的调转形式 * 达到简化代码的结果 * @author 玉姬 * */public class DispatcherServlet extends HttpServlet {	private static final long serialVersionUID = -2291078179694007198L;//	容器存放//	private Map
   
     actionMap=new HashMap
    
     ();	private ConfigModel configModel=null;//	url和uri的区别 地址区别//	url  :http://localhost:8080/T_mvc/cal.add.action//  uri  :T_mvc/cal.add.action		public void init() {//		初始化   //		actionMap.put("/cal_add", new AddCallAction());//发出请求//		actionMap.put("/cal_del", new DelCallAction());//发出请求//		actionMap.put("/cal_mul", new MulCallAction());//		actionMap.put("/cal_div", new DivCallAction());		try {			configModel=ConfigModelFactory.newInstance();		} catch (Exception e) {			// TODO Auto-generated catch block			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("."));//		AddCallAction action=(AddCallAction) actionMap.get(url);//		Action a=action;//		Action action=actionMap.get(url);//		action.execute(req, resp);		ActionModel actionModel=configModel.get(url);		try {			if(actionModel==null) {				throw new RuntimeException("你没有配置指定的子控制器来处理用户请求");			}			Action action=(Action) getClass().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。默认缺少项目名				resp.sendRedirect(req.getContextPath()+forwardModel.getPath());//重定向			}		} catch (InstantiationException e) {			// TODO Auto-generated catch block			e.printStackTrace();		} catch (IllegalAccessException e) {			// TODO Auto-generated catch block			e.printStackTrace();		} catch (ClassNotFoundException e) {			// TODO Auto-generated catch block			e.printStackTrace();		}		}	}
    
   

运行减法

3、 增强子控制器 将一组操作放到一个子控制器完成

package com.zxp.web;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import com.zxp.entity.Cal;import com.zxp.framework.Action;import com.zxp.framework.ActionSupport;public class CallAction extends ActionSupport {	public String add(HttpServletRequest req, HttpServletResponse resp)  {		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()));//		try {//			req.getRequestDispatcher("/rs.jsp").forward(req, resp);//		} catch (ServletException | IOException e) {//			// TODO Auto-generated catch block//			e.printStackTrace();//		}		return "rs";	}		public String del(HttpServletRequest req, HttpServletResponse resp)  {		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()));//		try {//			req.getRequestDispatcher("/rs.jsp").forward(req, resp);//		} catch (ServletException | IOException e) {//			// TODO Auto-generated catch block//			e.printStackTrace();//		}		return "rs";	}	public String mul(HttpServletRequest req, HttpServletResponse resp)  {		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()));//		try {//			req.getRequestDispatcher("/rs.jsp").forward(req, resp);//		} catch (ServletException | IOException e) {//			// TODO Auto-generated catch block//			e.printStackTrace();//		}		return "rs";	}	public String div(HttpServletRequest req, HttpServletResponse resp)  {		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()));//		try {//			req.getRequestDispatcher("/rs.jsp").forward(req, resp);//		} catch (ServletException | IOException e) {//			// TODO Auto-generated catch block//			e.printStackTrace();//		}		return "rs";	}}

增强版的子控制器

package com.zxp.framework;import java.lang.reflect.InvocationTargetException;import java.lang.reflect.Method;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;/** * 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 * @author 玉姬 * */public class ActionSupport implements Action {	@Override	public String execute(HttpServletRequest req, HttpServletResponse resp) {//		从前台传递需要调用的方法名到后台，实现动态方法调用		String methodName=req.getParameter("methodName");//		思考：如何获取到类实例		String code=null;		try {			Method m=this.getClass().getDeclaredMethod(methodName, HttpServletRequest.class,HttpServletResponse.class);			m.setAccessible(true);			try {				code=(String) m.invoke(this, req,resp);			} catch (IllegalAccessException | IllegalArgumentException | InvocationTargetException e) {				// TODO Auto-generated catch block				e.printStackTrace();			}		} catch (NoSuchMethodException | SecurityException e) {			e.printStackTrace();		}		return code;	}}

** 中央控制器**

package com.zxp.framework;import java.io.IOException;import java.util.HashMap;import java.util.Map;import javax.management.RuntimeErrorException;import javax.servlet.ServletException;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import com.zxp.web.AddCallAction;import com.zxp.web.DelCallAction;import com.zxp.web.DivCallAction;import com.zxp.web.MulCallAction;/** * 中央控制器 * 作用： * 接受用户请求，通过用户请求的url寻求指定的子控制器去处理业务 *  *  * 1.对存放子控制器action容器的增强 * 为什么：为了完成业务需求需要不断修改框架代码。这样设计是不合理的 * 处理：参照web.xml的实际方法，来完成中央控制管理子控制器的动态配置 *  * 2。处理结果码的调转形式 * 达到简化代码的结果 *  * 3.将一组操作放到一个子控制器完成 *  * 4.处理jsp传递到后台的参数封装 * @author 玉姬 * */public class DispatcherServlet extends HttpServlet {	private static final long serialVersionUID = -2291078179694007198L;//	容器存放//	private Map
   
     actionMap=new HashMap
    
     ();	private ConfigModel configModel=null;//	url和uri的区别 地址区别//	url  :http://localhost:8080/T_mvc/cal.add.action//  uri  :T_mvc/cal.add.action		public void init() {//		初始化   //		actionMap.put("/cal_add", new AddCallAction());//发出请求//		actionMap.put("/cal_del", new DelCallAction());//发出请求//		actionMap.put("/cal_mul", new MulCallAction());//		actionMap.put("/cal_div", new DivCallAction());		try {			configModel=ConfigModelFactory.newInstance();		} catch (Exception e) {			// TODO Auto-generated catch block			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("."));//		AddCallAction action=(AddCallAction) actionMap.get(url);//		Action a=action;//		Action action=actionMap.get(url);//		action.execute(req, resp);		ActionModel actionModel=configModel.get(url);		try {			if(actionModel==null) {				throw new RuntimeException("你没有配置指定的子控制器来处理用户请求");			}			Action action=(Action) getClass().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。默认缺少项目名				resp.sendRedirect(req.getContextPath()+forwardModel.getPath());//重定向			}		} catch (InstantiationException e) {			// TODO Auto-generated catch block			e.printStackTrace();		} catch (IllegalAccessException e) {			// TODO Auto-generated catch block			e.printStackTrace();		} catch (ClassNotFoundException e) {			// TODO Auto-generated catch block			e.printStackTrace();		}		}	}
    
   

配置

jsp页面

<%@ page language="java" contentType="text/html; charset=utf-8"    pageEncoding="utf-8"%>
   
   
    num1:
    
    
num2:
    
    
    +
    -
    *
    /
   

运行乘法

4、jsp参数封装增强 处理jsp传递到后台的参数封装 模型驱动接口

package com.zxp.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 * @author 玉姬 * * @param 
   
     */public interface ModelDriven
    
      {	T getModel();}
    
   

实现模型驱动接口

package com.zxp.web;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import com.zxp.entity.Cal;import com.zxp.framework.Action;import com.zxp.framework.ActionSupport;import com.zxp.framework.ModelDriven;public class CallAction extends ActionSupport implements ModelDriven
   
    {	private Cal cal=new Cal();	public String add(HttpServletRequest req, HttpServletResponse resp)  {//		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()));//		try {//			req.getRequestDispatcher("/rs.jsp").forward(req, resp);//		} catch (ServletException | IOException e) {//			// TODO Auto-generated catch block//			e.printStackTrace();//		}		return "rs";	}		public String del(HttpServletRequest req, HttpServletResponse resp)  {//		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()));//		try {//			req.getRequestDispatcher("/rs.jsp").forward(req, resp);//		} catch (ServletException | IOException e) {//			// TODO Auto-generated catch block//			e.printStackTrace();//		}		return "rs";	}	public String mul(HttpServletRequest req, HttpServletResponse resp)  {//		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()));//		try {//			req.getRequestDispatcher("/rs.jsp").forward(req, resp);//		} catch (ServletException | IOException e) {//			// TODO Auto-generated catch block//			e.printStackTrace();//		}		return "rs";	}	public String div(HttpServletRequest req, HttpServletResponse resp)  {//		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()));//		try {//			req.getRequestDispatcher("/rs.jsp").forward(req, resp);//		} catch (ServletException | IOException e) {//			// TODO Auto-generated catch block//			e.printStackTrace();//		}		return "rs";	}	@Override	public Cal getModel() {		// TODO Auto-generated method stub		return cal;	}}
   

给model赋值

package com.zxp.framework;import java.io.IOException;import java.lang.reflect.InvocationTargetException;import java.util.HashMap;import java.util.Map;import javax.management.RuntimeErrorException;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 org.apache.commons.beanutils.PropertyUtils;import com.zxp.entity.Cal;import com.zxp.web.AddCallAction;import com.zxp.web.DelCallAction;import com.zxp.web.DivCallAction;import com.zxp.web.MulCallAction;/** * 中央控制器 * 作用： * 接受用户请求，通过用户请求的url寻求指定的子控制器去处理业务 *  *  * 1.对存放子控制器action容器的增强 * 为什么：为了完成业务需求需要不断修改框架代码。这样设计是不合理的 * 处理：参照web.xml的实际方法，来完成中央控制管理子控制器的动态配置 *  * 2。处理结果码的调转形式 * 达到简化代码的结果 *  * 3.将一组操作放到一个子控制器完成 *  * 4.处理jsp传递到后台的参数封装 * @author 玉姬 * */public class DispatcherServlet extends HttpServlet {	private static final long serialVersionUID = -2291078179694007198L;//	容器存放//	private Map
   
     actionMap=new HashMap
    
     ();	private ConfigModel configModel=null;//	url和uri的区别 地址区别//	url  :http://localhost:8080/T_mvc/cal.add.action//  uri  :T_mvc/cal.add.action		public void init() {//		初始化   //		actionMap.put("/cal_add", new AddCallAction());//发出请求//		actionMap.put("/cal_del", new DelCallAction());//发出请求//		actionMap.put("/cal_mul", new MulCallAction());//		actionMap.put("/cal_div", new DivCallAction());		try {			configModel=ConfigModelFactory.newInstance();		} catch (Exception e) {			// TODO Auto-generated catch block			e.printStackTrace();		}	}	@Override	protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {		doPost(req, resp);	}	@SuppressWarnings("static-access")	@Override	protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {		String url=req.getRequestURI();		url=url.substring(url.lastIndexOf("/"),url.lastIndexOf("."));//		AddCallAction action=(AddCallAction) actionMap.get(url);//		Action a=action;//		Action action=actionMap.get(url);//		action.execute(req, resp);		ActionModel actionModel=configModel.get(url);		try {			if(actionModel==null) {				throw new RuntimeException("你没有配置指定的子控制器来处理用户请求");			}			Action action=(Action) getClass().forName(actionModel.getType()).newInstance();			if(action instanceof ModelDriven) {				ModelDriven modelDriven=(ModelDriven) action;				Object model=modelDriven.getModel();//				给model赋值意味着调用add/del方法时cal不在是空值				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。默认缺少项目名				resp.sendRedirect(req.getContextPath()+forwardModel.getPath());//重定向			}		} catch (InstantiationException e) {			// TODO Auto-generated catch block			e.printStackTrace();		} catch (IllegalAccessException e) {			// TODO Auto-generated catch block			e.printStackTrace();		} catch (ClassNotFoundException e) {			// TODO Auto-generated catch block			e.printStackTrace();		} catch (InvocationTargetException e) {			// TODO Auto-generated catch block			e.printStackTrace();		}		}	}
    
   

运行除法

5、框架配置文件可变

方法 （ <init-param> </init-param>）

   
     
    
     T_mvc
      
        
     
      cal.jsp
       
      
      
     
      dispatcherServlet
       
     
      com.zxp.framework.DispatcherServlet
       
       
      
       mvcXmlLocation
        
      
       /yu.xml
        
       
      
      
     
      dispatcherServlet
       
     
      *.action
       
      
   

调用

写在中央控制器

//			解决框架配置文件重名冲突问题			String mvcXmlLocation=this.getInitParameter("mvcXmlLocation");			if(null==mvcXmlLocation||"".equals("mvcXmlLocation")) {				mvcXmlLocation="mvc.xml";			}			System.out.println(mvcXmlLocation);

冲突

不冲突

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