MVC架构的学习

1：结构介绍

 

 

2：代码实现

2.1：M

package bean;

/**
 * @author ：dazhu
 * @date ：Created in 2020/4/30 16:25
 * @description：数据库boys表的记录对象
 * @modified By：
 * @version: $
 */
public class Boy {
    public int id;
    public String name;
    public int userCP;

    public Boy(){
    }
    public Boy(int id,String name,int userCP){
        this.id = id;
        this.name = name;
        this.userCP = userCP;
    }

    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public int getUserCP() {
        return userCP;
    }

    public void setUserCP(int userCP) {
        this.userCP = userCP;
    }
}

注意在这里要对字段实现setter和getter方法，因为在jsp中，要默认通过这两个方法来获取模型字段。

2.2：V

<%@ page language="java" contentType="text/html; charset=UTF-8"
         pageEncoding="UTF-8" import="java.util.*"%>

<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>

<table align='center' border='10' cellspacing='10'>
    <tr>
        <td>id</td>
        <td>name</td>
        <td>userCP</td>
    </tr>
    <c:forEach items="${boys}" var="boy" varStatus="st">
        <tr>
            <td>${boy.id}</td>
            <td>${boy.name}</td>
            <td>${boy.userCP}</td>
        </tr>
    </c:forEach>
</table>

在servlet中将结果集合放进来，进行处理和展示。

2.3：C

package MVC;

import bean.Boy;
import dao.BoyDAO;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.util.List;

/**
 * @author ：dazhu
 * @date ：Created in 2020/5/4 8:36
 * @description：
 * @modified By：
 * @version: $
 */
public class boyListServlet extends HttpServlet{
    protected void service(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        List<Boy> boys = new BoyDAO().list();
        request.setAttribute("boys", boys);
        request.getRequestDispatcher("boyList.jsp").forward(request, response);
    }
}

通过访问servlet来进行后端数据侧处理。