自定义MVC(一)

最新推荐文章于 2022-07-17 21:36:29 发布

原创最新推荐文章于 2022-07-17 21:36:29 发布 · 179 阅读

0 ·

CC 4.0 BY-SA版权

文章标签：

#MVC

自定义mvc

1.什么是MVC
2.MVC结构
3.思维导图
4.案例
5.总结

1.什么是MVC

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

M: 1. 实体域模型(名词)
2.过程域模型(动词)

V:做浏览器请求分发 jsp/ios/android

C:操作数据库 servlet/action

3.思维导图

在这里插入图片描述

4.案例

做一个加减乘除的案例

下面咋们就开始了
1.从实体类开始

package com.yinyi.entity;

public class Cal {

	private String num1;
	private String num2;
	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();
	}
	
	
}

2.定义主控制器

package com.yinyi.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.yinyi.web.AddCalAction;
import com.yinyi.web.DelCalAction2;
import com.yinyi.web.chengfaCalAction3;
import com.yinyi.web.chufaCalAction3;

/**
 * 主控制器
 * @author yinyi
 *
 */
public class DispathcherServlet extends HttpServlet {
	
	private static final long serialVersionUID = 1718695479595952099L;
	private Map<String , Action> actionMap = new HashMap<>();
	
	public void init() {
		actionMap.put("/addCal", new AddCalAction());//加
		actionMap.put("/delCal", new DelCalAction2());//减
		actionMap.put("/chengfaCal", new chengfaCalAction3());//乘
		actionMap.put("/chufalCal", new chufaCalAction3());//除
		 
	}
	
		@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 {
		init();
		String url = req.getRequestURI();//T224_mvc/xxx/action
		url = url.substring(url.lastIndexOf("/"),url.lastIndexOf("."));
		Action action = actionMap.get(url);
		action.execute(req, resp);
		}
}

3.定义子控制器

package com.yinyi.framework;

import java.io.IOException;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**
 * 子控制器
 * 专门用来处理业务逻辑的
 * @author yinyi
 *
 */
public interface Action {
	 void execute(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException;
 
}

4.写加减乘除

1.加
@Override
	public void execute(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
		String num1 = req.getParameter("num1");
		String num2 = req.getParameter("num2");
		req.setAttribute("res", Integer.valueOf(num1)+Integer.valueOf(num2));
		req.getRequestDispatcher("calRes.jsp").forward(req, resp);

	}
	
2.减
public void execute(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
		String num1 = req.getParameter("num1");
		String num2 = req.getParameter("num2");
		req.setAttribute("res", Integer.valueOf(num1)-Integer.valueOf(num2));
		req.getRequestDispatcher("calRes.jsp").forward(req, resp);

	}

3.乘
public void execute(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
		String num1 = req.getParameter("num1");
		String num2 = req.getParameter("num2");
		req.setAttribute("res", Integer.valueOf(num1)*Integer.valueOf(num2));
		req.getRequestDispatcher("calRes.jsp").forward(req, resp);

	}

4.除
public void execute(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
		String num1 = req.getParameter("num1");
		String num2 = req.getParameter("num2");
		req.setAttribute("res", Integer.valueOf(num1)/Integer.valueOf(num2));
		req.getRequestDispatcher("calRes.jsp").forward(req, resp);

	}

5.发送请求

<%@ 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=ISO-8859-1">
<title>Insert title here</title>
<script type="text/javascript">
	function dosub(val) {
		if(val ==1){
			calForm.action = "${pageContext.request.contextPath }/addCal.action";
		}
		else if(val ==2){
			calForm.action = "${pageContext.request.contextPath }/delCal.action";
		}
		else if(val ==3){
			calForm.action = "${pageContext.request.contextPath }/chengfaCal.action";
		}
		else{
			calForm.action = "${pageContext.request.contextPath }/chufalCal.action";
		}
		calForm.submit();
	}
</script>
</head>
<body>
	<form id="calForm" name="calForm"    action="${pageContext.request.contextPath }/addCal.action">
		num1:<input type="text" name="num1"><br>
		num2:<input type="text" name="num2"><br>
		<button οnclick="dosub(1)">+</button>
		<button οnclick="dosub(2)">-</button>
		<button οnclick="dosub(3)">X</button>
		<button οnclick="dosub(4)">/</button>
	</form>
</body>
</html>

6.跳转页面

<%@ 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=ISO-8859-1">
<title>Insert title here</title>

</head>
<body>
结果: ${res }
</body>
</html>

7.配置XML

 <servlet>
  	<servlet-name>dispathcherServlet</servlet-name>
  	<servlet-class>com.yinyi.framework.DispathcherServlet</servlet-class>
  </servlet>
  <servlet-mapping>
  	<servlet-name>dispathcherServlet</servlet-name>
  	<url-pattern>*.action</url-pattern>
  </servlet-mapping>