java web mvc思想介绍

1、首先简介一下什么是MVC思想。

在百度百科里面对MVC的说明，MVC全名是Model View Controller。是模型(model)－视图(view)－控制器(controller)的缩写。那么在JAVA的web开发中。MVC各自是相应于：显示页面（视图）、数据对象（模型）、业务处理（控制器）。

简单举个样例来说，在学生信息管理系统里。登陆界面就是一个视图。而登陆完毕后。进行username和password推断并跳转对应的页面，就是控制器，而保存username和password的对象，就是模型。三者的关系就是这样。

我们以下给出了一个java动态网页的样例。

2、文件结构



3、所要用到的

tomcat7.0

4、代码结构

UserCheck

package com.test.dao;

import com.test.vo.User;

public class UserCheck {

public boolean login(User user)
{
if(user.getUsername().equals("admin") && user.getPassword().equals("123456"))
return true;
return false;
}

}

UserLogin

package com.test.service;

import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import com.test.dao.UserCheck;
import com.test.vo.User;

/**
* Servlet implementation class UserLogin
*/
@WebServlet("/UserLogin")
public class UserLogin extends HttpServlet {
private static final long serialVersionUID = 1L;

/**
* Default constructor.
*/
public UserLogin() {
// TODO Auto-generated constructor stub
}

/**
* @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
*/
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
}

/**
* @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
*/
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
User u=new User();
u.setUsername(request.getParameter("username"));
u.setPassword(request.getParameter("password"));
System.out.println(request.getParameter("username")+" "+request.getParameter("password"));
UserCheck dao=new UserCheck();
if(dao.login(u))
{
response.sendRedirect("login_s.jsp");
}
else
{
response.sendRedirect("login_f.jsp");
}

}

}

User

package com.test.vo;

public class User {

private String username;
public String getUsername() {
return username;
}
public void setUsername(String username) {
this.username = username;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
private String password;
}

静态页面比較简单，就不贴上来了。