100字范文 > MVC框架实现用户登录注册功能（连接数据库）

MVC框架实现用户登录注册功能（连接数据库）

时间：2021-10-22 13:28:22

一、简单理解MVC框架

经典MVC模式中，M是指业务模型，V是指用户界面，C则是控制器，使用MVC的目的是将M和V的实现代码分离，从而使同一个程序可以使用不同的表现形式。

其中，View的定义比较清晰，就是用户界面。Model即对数据进行逻辑处理的部分。Controller按照用户请求来选择对应的Model进行处理同时把处理结果返回到指定的jsp视图中，只是接收请求并决定调用哪个模型构件去处理请求，然后再确定用哪个视图来显示返回的数据。

二、项目结构

三、项目源码

3.1 User

代码如下（示例）：

public class User {// 封装实体类的JavaBeanprivate String name;private String password;public User() {}// 构造方法用来传入数值public User(String name, String password) {this.name = name;this.password = password;}public String getName() {return name;}public void setName(String name) {this.name = name;}public String getPassword() {return password;}public void setPassword(String password) {this.password = password;}}

3.2UserDao

代码如下（示例）：

import java.sql.*;//处理业务逻辑的JavaBeanpublic class UserDao {public static int login(User user) {int flag = -1;String NAME = "sa";String PASSWORD = "123456";String URL = "jdbc:sqlserver://localhost:1433;databaseName=test";Connection connection = null;PreparedStatement pstmt = null;ResultSet rs = null;try {// 1、加载驱动Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");// 2、建立连接connection = DriverManager.getConnection(URL, NAME, PASSWORD);// 3、操作数据库String sql = "select count(*) from admins where name=? and password=?";pstmt = connection.prepareStatement(sql);pstmt.setString(1, user.getName());pstmt.setString(2, user.getPassword());// 4、执行rs = pstmt.executeQuery();if (rs.next()) {flag = rs.getInt(1);}if (flag > 0) {// 登录成功return 1;} else {return 0;}} catch (ClassNotFoundException e) {e.printStackTrace();return -1;} catch (SQLException e) {e.printStackTrace();return -1;} catch (Exception e) {e.printStackTrace();return -1;} finally {try {if (rs != null) rs.close();if (pstmt != null) pstmt.close();if (connection != null) connection.close();} catch (SQLException e) {e.printStackTrace();} catch (Exception e) {e.printStackTrace();}}}}

3.3RegisterDao

代码如下（示例）：

import java.sql.*;//封装注册功能业务逻辑的JavaBeanpublic class RegisterDao {public static int register(User user) {int count = -1;String NAME = "sa";String PASSWORD = "123456";String URL = "jdbc:sqlserver://localhost:1433;databaseName=test";Connection connection = null;PreparedStatement pstmt = null;ResultSet rs = null;try {//1、加载驱动Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");//2、连接connection = DriverManager.getConnection(URL, NAME, PASSWORD);//操作数据库String sql = "insert into admins values(?,?)";//插入数据pstmt = connection.prepareStatement(sql);pstmt.setString(1, user.getName());pstmt.setString(2, user.getPassword());count = pstmt.executeUpdate();return count;} catch (ClassNotFoundException e) {e.printStackTrace();return -1;} catch (SQLException e) {e.printStackTrace();return -1;} catch (Exception e) {e.printStackTrace();return -1;} finally {try {if (pstmt != null) pstmt.close();if (connection != null) connection.close();} catch (Exception e) {e.printStackTrace();}}}}

3.4servletControll

代码如下（示例）：

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 java.io.IOException;/*** Servlet implementation class servletControll*/@WebServlet("/servletControll")public class servletControll extends HttpServlet {private static final long serialVersionUID = 1L;protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {//取值request.setCharacterEncoding("utf-8");String name = request.getParameter("uname");String pwd = request.getParameter("upwd");//封装User user = new User(name, pwd);//调用业务逻辑层int result = UserDao.login(user);if (result > 0) {//登录成功response.sendRedirect("success.jsp");//重定向到成功界面} else {//登录失败response.sendRedirect("notsuccess.jsp");//定位到失败页面}//请求转发}protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {doGet(request, response);}}

3.5 servletControllRegister

代码如下（示例）：

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 java.io.IOException;/*** Servlet implementation class servletControllRegister*/@WebServlet("/servletControllRegister")public class servletControllRegister extends HttpServlet {private static final long serialVersionUID = 1L;protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {//注册功能、、向数据库添加数据request.setCharacterEncoding("utf-8");String name = request.getParameter("uname");String pwd = request.getParameter("upwd");User user = new User(name, pwd);//保存客户端输入的信息int result = RegisterDao.register(user);if (result > 0) {//注册成功response.sendRedirect("login.jsp");} else {//注册失败重新注册response.sendRedirect("register.jsp");}}protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {doGet(request, response);}}

3.6web.xml

代码如下（示例）：

<?xml version="1.0" encoding="UTF-8"?><web-app xmlns="/xml/ns/javaee"xmlns:xsi="/2001/XMLSchema-instance"xsi:schemaLocation="/xml/ns/javaee /xml/ns/javaee/web-app_4_0.xsd"version="4.0"><welcome-file-list><welcome-file>login.jsp</welcome-file></welcome-file-list><servlet><servlet-name>Login</servlet-name><servlet-class>servletControll</servlet-class></servlet><servlet-mapping><servlet-name>Login</servlet-name><url-pattern>/user</url-pattern></servlet-mapping><servlet><servlet-name>Register</servlet-name><servlet-class>servletControllRegister</servlet-class></servlet><servlet-mapping><servlet-name>Register</servlet-name><url-pattern>/register</url-pattern></servlet-mapping></web-app>

3.7login.jsp

代码如下（示例）：

<%--Created by IntelliJ IDEA.User: 10504Date: /5/17Time: 12:49To change this template use File | Settings | File Templates.--%>登录页面<%@ page language="java" contentType="text/html; charset=UTF-8"pageEncoding="UTF-8" %><!DOCTYPE html><html><head><meta charset="UTF-8"><title>登录页面</title></head><body><form action="servletControll" method="post">用户名：<input type="text" name="uname"/>密码：<input type="password" name="upwd"/><br><br><input type="submit" value="登录"/><input type="reset" value="重置"/><a href="register.jsp">注册新用户</a></form></body></html>

3.8register.jsp

代码如下（示例）：

<%--Created by IntelliJ IDEA.User: 10504Date: /5/17Time: 12:55To change this template use File | Settings | File Templates.--%>注册页面<%@ page language="java" contentType="text/html; charset=UTF-8"pageEncoding="UTF-8" %><!DOCTYPE html><html><head><meta charset="UTF-8"><title>注册页面</title></head><body><form action="servletControllRegister" method="post">用户名：<input type="text" name="uname"/>密码：<input type="password" name="upwd"/><input type="submit" value="注册"/></form></body></html>

3.9success.jsp

代码如下（示例）：

<%--Created by IntelliJ IDEA.User: 10504Date: /5/17Time: 13:29To change this template use File | Settings | File Templates.--%><%@ page contentType="text/html;charset=UTF-8" language="java" %><html><head><title>登录成功</title></head><body>欢迎您的使用！</body></html>

3.10failure.jsp

代码如下（示例）：

<%--Created by IntelliJ IDEA.User: 10504Date: /5/17Time: 13:42To change this template use File | Settings | File Templates.--%><%@ page contentType="text/html;charset=UTF-8" language="java" %><html><head><title>登录失败</title></head><body></body></html>