基于jsp+servlet的javaweb实现最基本的用户注册登陆注销功能

本案例的技术选型主要是jsp+servlet+JavaBean，采用三层架构的分层思想与MVC设计模式结合进行规范开发。

采用的数据库是MySQL，并且搭配数据源连接池DBCP和apache官方提供的DBUtils进行数据库连接开发。

目的是为了简化SQL连接编码，并且提高连接数据库的性能。

以下是DBUtils1.7版本的分享链接：https://pan.baidu.com/s/1Ohg9v-vN2m3lwP_BSizrGA      提取码：idca

POOL的组件官方最新下载地址：http://commons.apache.org/proper/commons-pool/download_pool.cgi

以下是DBCP和POOL最新版本的分享链接：https://pan.baidu.com/s/1tR5LAT5v2B94_d0wACCvSA     提取码：3e5o

1. 先设计数据库，有两种方式：

a）编写SQL代码[推荐]：

1. 创建sql文件：

2. 编写SQL代码：

-- 创建数据库
create database login;
-- 选择数据库
use login;
-- 创建用户表
create table user(
	id int primary key auto_increment, -- 用户编号 - 主键（自动递增）
	username varcahr(30),	-- 用户名
	password varcahr(30), 	-- 用户密码
	email varcahr(50),		-- 用户邮箱
	sex  varcahr(50)	-- 用户性别 [注：最后一个字段，不要再最后加入“,”]
);

3. 使用代码进行执行建表！

b）使用可视化窗口进行建表

???

2. 开始写实体类：User.java

package cn.javabs.login.entity;

/**
 * Title: User.java
 * @date 2018年10月5日 下午3:19:40
 * @author Mr.yang
 * 用户的实体类设计
 */
public class User {

	private Integer id;

	private String username;

	private String password;

	private String sex;

	private String email;

	public Integer getId() {
		return id;
	}

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

	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;
	}

	public String getEmail() {
		return email;
	}

	public void setEmail(String email) {
		this.email = email;
	}

	public String getSex() {
		return sex;
	}

	public void setSex(String sex) {
		this.sex = sex;
	}
}

　　3.接下来写的是DAO的接口

package cn.javabs.login.dao;

import java.sql.SQLException;

import cn.javabs.login.entity.User;

/**
 * Title: UserDao.java
 * @date 2018年10月5日 下午3:24:55
 * @author Mr.yang
 * 用户的DAO接口设计
 * 			|--- 接口是不可以被final修饰的哦！
 * 		|--- 登录
 * 		|--- 注册
 */
public interface UserDao {

	/**
	 * 用户登录（需要传入两个参数）
	 * @param username 用户名
	 * @param password 密码
	 * @return	用户对象
	 * @throws SQLException
	 */
	User login(String username,String password) throws SQLException;

	/**
	 * 用户注册（传入的是对象）
	 * @param user
	 * @return 整数
	 * @throws SQLException
	 */
	int regist(User user) throws SQLException;

}

　　4.接下来写的是DAO的实现类

package cn.javabs.login.dao.impl;

import java.sql.SQLException;

import org.apache.commons.dbutils.QueryRunner;
import org.apache.commons.dbutils.handlers.BeanHandler;

import cn.javabs.login.dao.UserDao;
import cn.javabs.login.entity.User;
import cn.javabs.login.util.DBCPUtils;

/**
 * Title: UserDaoImpl.java
 * 用户的DAO实现类的设计
 * @date 2018年10月5日 下午3:28:33
 * @author Mr.yang 采用[数据源连接池 - DBCP] 使用Dbutils工具类中的QueryRunner进行
 */
public class UserDaoImpl implements UserDao {

	QueryRunner queryRunner = new QueryRunner(DBCPUtils.getDataSource());

	@Override
	public User login(String username, String password) throws SQLException {
		return queryRunner.query(
				"select * from user where username = ? and password = ?", //
				new BeanHandler<User>(User.class), username, password);
	}

	@Override
	public int regist(User user) throws SQLException {

		return queryRunner.update("insert into user(username,password,sex,email)values(?,?,?,?)",
				user.getUsername(),
				user.getPassword(),
				user.getSex(),
				user.getEmail()
				);

	}

}

　　5.接下来需要把DAO中的用到的数据源连接池的工具类补全

package cn.javabs.login.util;

import java.io.InputStream;
import java.sql.Connection;
import java.sql.SQLException;
import java.util.Properties;

import javax.sql.DataSource;

import org.apache.commons.dbcp2.BasicDataSourceFactory;

/**
 * Title: DBCPUtils.java
 *
 * @date 2018年10月5日 下午4:04:48
 * @author Mr.yang
 */
public class DBCPUtils {

	public static DataSource dataSource;

	static {

		try {
			String resource = "jdbc.properties";
			InputStream is = DBCPUtils.class.getClassLoader()
					.getResourceAsStream(resource);
			Properties properties = new Properties();
			properties.load(is);
			dataSource = BasicDataSourceFactory.createDataSource(properties);
		} catch (Exception e) {
			throw new RuntimeException(e);
		}

	}

	/**
	 * 获取数据源
	 * @return
	 */
	public static DataSource getDataSource() {
		return dataSource;
	}

	/**
	 * 获取连接
	 * @return
	 */
	public static Connection getConnection() {
		try {
			return dataSource.getConnection();
		} catch (SQLException e) {
			throw new RuntimeException(e);
		}
	}

}

　　5.2 在config的中创建配置文件:jdbc.properties

driverClassName = com.mysql.jdbc.Driver
url = jdbc:mysql:///login
username = root
password = sorry

# 初始化连接
initialSize=10
# 最大连接数量
maxActive=50
# 最大空闲数量
maxIdle=20
# 最小空闲数量
minIdle=5

　　6. 接下来把service层的接口设计出来

package cn.javabs.login.service;

import cn.javabs.login.entity.User;

/**
 * Title: UserService.java
 * @date 2018年10月5日 下午4:15:04
 * @author Mr.yang
 */
public interface UserService {

	/**
	 * 用户登录（传入两个参数，用户名和密码）
	 * @param username
	 * @param password
	 * @return 用户对象
	 */
	User userLogin(String username,String password);

	/**
	 * 用户注册（传入的是对象）
	 * @param user
	 * @return 影响的行数
	 */
	int userRegister(User user);
}

　　7.接下来把service层的实现类设计出来

package cn.javabs.login.service.impl;

import java.sql.SQLException;

import cn.javabs.login.dao.UserDao;
import cn.javabs.login.dao.impl.UserDaoImpl;
import cn.javabs.login.entity.User;
import cn.javabs.login.service.UserService;

/**
 * Title: UserServiceImpl.java
 * @date 2018年10月5日 下午4:17:34
 * @author Mr.yang
 */
public class UserServiceImpl implements UserService {

	UserDao userDao = new UserDaoImpl();

	@Override
	public User userLogin(String username, String password) {

		try {
			User user = userDao.login(username, password);
			return user;
		} catch (SQLException e) {
			throw new RuntimeException(e);
		}

	}

	@Override
	public int userRegister(User user) {
		try {
			return userDao.regist(user);
		} catch (SQLException e) {
			throw new RuntimeException(e);
		}
	}
}

　　8.接下来把controller层的控制器设计出来

package cn.javabs.login.controller;

import java.io.IOException;

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

import org.apache.commons.lang3.StringUtils;

import cn.javabs.login.entity.User;
import cn.javabs.login.service.UserService;
import cn.javabs.login.service.impl.UserServiceImpl;

/**
 *
 * @author Mryang StringUtilsz中的isNotbBlock：判断某字符串是否不为空且长度不为0且不由空白符构成
 *
 */
public class UserServlet extends HttpServlet {
	private static final long serialVersionUID = 1L;

	// 引入UserService
	UserService userService = new UserServiceImpl();

	protected void doGet(HttpServletRequest request,
			HttpServletResponse response) throws ServletException, IOException {
		doPost(request, response);
	}

	protected void doPost(HttpServletRequest request,
			HttpServletResponse response) throws ServletException, IOException {

		String method = request.getParameter("method");

		// 如果传入的参数是login
		if ("login".equals(method)) {
			login(request, response);
			// 如果传入的参数是regist
		} else if ("regist".equals(method)) {
			regist(request, response);
			// 如果传入的参数是logout
		} else if ("logout".equals(method)) {
			logout(request, response);
			// 如果传入的参数是tologin
		} else if ("tologin".equals(method)) {
			tologin(request, response);
			// 如果传入的参数是toregist
		} else if ("toregist".equals(method)) {
			toregist(request, response);
			// 如果传入的参数是对应不上
		} else {
			request.setAttribute("msg", "该功能正在开发...");
			request.getRequestDispatcher("/message.jsp").forward(request, response);
		}

	}

	/**
	 * 用户登录
	 *
	 * @param request
	 * @param response
	 */
	private void login(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {
		/*
		 * 1. 获取前台jsp表单传递的参数
		 */
		String username = request.getParameter("username");
		String password = request.getParameter("password");

		// 如果测试传入的参数。可以打开72行的注释
		// System.out.println("用户名：" + username + "<br/>" + "密码" + password);

		/*
		 * 2.根据参数进行判断
		 */
		// 2.1 如果用户名和密码都不为空
		if (StringUtils.isNotBlank(username)
				&& StringUtils.isNotBlank(password)) {
			// 2.1.1 传递到service层登录方法
			User user = userService.userLogin(username, password);
			// 2.1.2 判断用户信息是否查询到
			if (user != null) {
				// 查询到，存入session
				request.getSession().setAttribute("USER_SESSION", user);
				// 登录成功，转向主页
				request.getRequestDispatcher("/WEB-INF/jsp/main.jsp").forward(
						request, response);
			} else {
				// 未查询到或者用户名和密码不匹配，将失败的信息存储到msg中
				request.setAttribute("msg", "用户名或者密码不对！");
				// 登录失败，转向错误信息提示页面，根据存入的msg取出相对应的内容
				request.getRequestDispatcher("/message.jsp").forward(request,
						response);//
			}
			// 2.2 如果用户名或者密码为空
		} else {
			request.setAttribute("msg", "用户名或者密码不许为空！");
			request.getRequestDispatcher("/WEB-INF/jsp/login.jsp").forward(
					request, response);//
		}

	}

	/**
	 * 用户注册
	 *
	 * @param request
	 * @param response
	 * @throws ServletException
	 * @throws IOException
	 */
	private void regist(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {

		User user = new User();

		// 1. 获取前台jsp页面的参数
		String username = request.getParameter("username");
		String password = request.getParameter("password");
		String sex = request.getParameter("sex");
		String email = request.getParameter("email");

		// 2. 将获取到的参数封装到user对象中去
		user.setUsername(username);
		user.setPassword(password);
		user.setEmail(email);
		user.setSex(sex);

		if (StringUtils.isNotBlank(user.getUsername())
				&& StringUtils.isNotBlank(user.getPassword())) {

			int rows = userService.userRegister(user);
			if (rows > 0) {
				response.setHeader("refresh",
						"1;url=UserServlet?method=tologin");
			} else {
				request.setAttribute("msg", "注册失败！");
				request.getRequestDispatcher("/message").forward(request,
						response);
			}
		}else{
			request.setAttribute("msg", "用户名或者密码不许为空");
			request.getRequestDispatcher("/message").forward(request,
					response);
		}

	}

	/**
	 * 转向到登录页面
	 *
	 * @param request
	 * @param response
	 * @throws ServletException
	 * @throws IOException
	 */
	private void tologin(HttpServletRequest request,
			HttpServletResponse response) throws ServletException, IOException {
		request.getRequestDispatcher("/WEB-INF/jsp/login.jsp").forward(request,
				response);//
	}

	/**
	 * 转向到注册页面
	 *
	 * @param request
	 * @param response
	 * @throws ServletException
	 * @throws IOException
	 */
	private void toregist(HttpServletRequest request,
			HttpServletResponse response) throws ServletException, IOException {
		request.getRequestDispatcher("/WEB-INF/jsp/regist.jsp").forward(
				request, response);//
	}

	/**
	 * 用户注销
	 * @param request
	 * @param response
	 * @throws ServletException
	 * @throws IOException
	 */
	private void logout(HttpServletRequest request,
			HttpServletResponse response) throws ServletException, IOException {
		request.getSession().invalidate();
		request.getRequestDispatcher("/WEB-INF/jsp/login.jsp").forward(
				request, response);//
	}

}

　　9. jsp页面开发

　　　　-- 9.1 首页index.jsp　　　　

<%@ 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=UTF-8">
<title>Insert title here</title>
</head>
<body>
    <jsp:forward page="WEB-INF/jsp/regist.jsp"></jsp:forward>
</body>
</html>

　　9.2 登录页面 在WEB-INF中新建一个Folder，起名为jsp，在jsp文件夹中新建 login.jsp

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head>
	<meta charset="utf-8" />
	<meta name="viewport" content="width=device-width, initial-scale=1.0">
	<title></title>
	<link rel="stylesheet" href="css/reset.css" />
	<link rel="stylesheet" href="css/login.css" />
        <script type="text/javascript" src="js/jquery.min.js"></script>
	<style type="text/css">
		#err{
			color: red;
			margin-left: 115px;
			margin-top: 25px;
			padding-top: 22px;
		}
		#toregist{
				margin-left: 280px;
				font-size: 14px;
				text-decoration: none;
				color:deepskyblue;
		}
		a:HOVER {
			color:red;
			font-size: 15px;
			text-decoration: underline;
		}
	</style>
</head>
<body>
<div class="page">
	<div class="loginwarrp">
		<div class="logo">管理员登陆</div>
		<br />
		<span id="err">${msg }</span><!-- 错误信息提示  -->
		<a id="toregist" href="${pageContext.request.contextPath}/UserServlet?method=toregist">没有账号，去注册</a>
        <div class="login_form">
			<form id="Login" name="Login" method="post"  action="${pageContext.request.contextPath}/UserServlet?method=login">
				<li class="login-item">
					<span>用户名：</span>
					<input type="text" id="username" name="username" class="login_input" >
                                        <span id="count-msg" class="error"></span>
				</li>
				<li class="login-item">
					<span>密　码：</span>
					<input type="password" id="password" name="password" class="login_input" >
                                        <span id="password-msg" class="error"></span>
				</li>
				<!--
				<li class="login-item verify">
					<span>验证码：</span>
					<input type="text" name="CheckCode" class="login_input verify_input">
				</li>
				<img src="images/verify.png" border="0" class="verifyimg" />
				-->
				<div class="clearfix"></div>
				<li class="login-sub">
					<input type="submit" name="Submit" value="登录" />
                                        <input type="reset" name="Reset" value="重置" />
				</li>
           </form>
		</div>
	</div>
</div>
<script type="text/javascript">
		window.onload = function() {
			var config = {
				vx : 4,
				vy : 4,
				height : 2,
				width : 2,
				count : 100,
				color : "121, 162, 185",
				stroke : "100, 200, 180",
				dist : 6000,
				e_dist : 20000,
				max_conn : 10
			}
			CanvasParticle(config);
		}
	</script>
	<script type="text/javascript" src="js/canvas-particle.js"></script>
</body>
</html>

　　9.3 注册页面 在WEB-INF中新建一个Folder，起名为jsp，在jsp文件夹中新建 regist.jsp

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
	<head>
		<title>${initParam.MyTitle}</title>

		<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
		<meta name="viewport" content="width=device-width, initial-scale=1.0, minimum-scale=1.0">

		<link rel="stylesheet" href="css/demo.css">
		<link rel="stylesheet" href="css/sky-forms.css">
		<link rel="stylesheet" href="css/sky-forms-ie8.css">
		<script src="js/jquery-1.9.1.min.js"></script>
		<script src="js/jquery.validate.min.js"></script>
		<script src="js/jquery.placeholder.min.js"></script>
		<script src="http://html5shim.googlecode.com/svn/trunk/html5.js"></script>
		<script src="js/sky-forms-ie8.js"></script>
		<style type="text/css">
			#tologin{
				margin-left: 220px;
				font-size: 14px;
				text-decoration: none;
			}
			a:HOVER {
				color:red;
				font-size: 15px;
				text-decoration: underline;
			}
		</style>
	</head>

	<body class="bg-cyan">
		<div class="body body-s">
			<form action="${pageContext.request.contextPath}/UserServlet?method=regist" method="post" id="sky-form" class="sky-form">
				<header>请填写表单</header>
				<fieldset>					<!--  -->
					<a id="tologin" href="${pageContext.request.contextPath}/UserServlet?method=tologin">已有账号，去登录</a>
					<br />
					<br />
					<section>
						<label class="input">
							<i class="icon-append icon-user"></i>
							<input type="text" name="username" placeholder="用户名">
							<b class="tooltip tooltip-bottom-right">请输入用户名</b>
						</label>
					</section>

					<section>
						<label class="input">
							<i class="icon-append icon-envelope-alt"></i>
							<input type="email" name="email" placeholder="Email">
							<b class="tooltip tooltip-bottom-right">请输入您的Email地址</b>
						</label>
					</section>

					<section>
						<label class="input">
							<i class="icon-append icon-lock"></i>
							<input type="password" name="password" placeholder="密码" id="password">
							<b class="tooltip tooltip-bottom-right">请输入您的密码</b>
						</label>
					</section>

					<section>
						<label class="input">
							<i class="icon-append icon-lock"></i>
							<input type="password" name="passwordConfirm" placeholder="请再次输入您的密码">
							<b class="tooltip tooltip-bottom-right">请再次输入您的密码</b>
						</label>
					</section>

					<section>
						<label class="select">
							<select name="sex">
								<option value="0" selected disabled>请选择性别</option>
								<option value="1">男性</option>
								<option value="2">女性</option>

							</select>
							<i></i>
						</label>
					</section>
				</fieldset>
				<fieldset>

					<section>
						<label class="checkbox"><input type="checkbox" name="subscription" id="subscription"><i></i>I
					我愿意接受互联网研习社最新动态</label>
						<label class="checkbox"><input type="checkbox" name="terms" id="terms"><i></i>I
					我同意注册许可</label>
					</section>
				</fieldset>
				<footer>
					<button type="submit" class="button">提交注册</button>
				</footer>
			</form>
		</div>

		<script type="text/javascript">
			$(function()
			{
				// Validation
				$("#sky-form").validate(
				{
					// Rules for form validation
					rules:
					{
						username:
						{
							required: true
						},
						email:
						{
							required: true,
							email: true
						},
						password:
						{
							required: true,
							minlength: 3,
							maxlength: 20
						},
						passwordConfirm:
						{
							required: true,
							minlength: 3,
							maxlength: 20,
							equalTo: ‘#password‘
						},
						firstname:
						{
							required: true
						},
						lastname:
						{
							required: true
						},
						gender:
						{
							required: true
						},
						terms:
						{
							required: true
						}
					},

					// Messages for form validation
					messages:
					{
						login:
						{
							required: ‘Please enter your login‘
						},
						email:
						{
							required: ‘Please enter your email address‘,
							email: ‘Please enter a VALID email address‘
						},
						password:
						{
							required: ‘Please enter your password‘
						},
						passwordConfirm:
						{
							required: ‘Please enter your password one more time‘,
							equalTo: ‘Please enter the same password as above‘
						},
						firstname:
						{
							required: ‘Please select your first name‘
						},
						lastname:
						{
							required: ‘Please select your last name‘
						},
						gender:
						{
							required: ‘Please select your gender‘
						},
						terms:
						{
							required: ‘You must agree with Terms and Conditions‘
						}
					},					

					// Do not change code below
					errorPlacement: function(error, element)
					{
						error.insertAfter(element.parent());
					}
				});
			});
		</script>
 <div style="width:960px;margin:10px auto; clear:both; text-align:center;  ">
<script src="/statics/js/ad/96090.js" type="text/javascript"></script>
</div>
<div style="width:960px;margin:20px auto; clear:both; text-align:center; font-size:12px; line-height:25px;    ">
<a href="https://blog.csdn.net/kese7952"  style="color:#333"><strong>Mryang个人整理</strong></a> </strong>
 转载请自觉注明出处！注：此代码仅供学习交流，请勿用于商业用途。
<br>
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alt="编程研习社QQ群①" title="编程研习社QQ群①"></a>
<script src="/statics/js/inc_share.js"  type="text/javascript"></script>
<script src="/statics/js/inc_statistics.js"  type="text/javascript"></script>
<script src="/statics/js/inc_monitor.js"  type="text/javascript"></script>
</div>
	</body>
</html>

　　9.4.登录成功页面

<%@ 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=UTF-8">
<title>Insert title here</title>
</head>
<body>

	<center>
		<h3>
			${sessionScope.USER_SESSION.username},遇到您真好!
		</h3>
		<hr/>
		<h4>
			<a href="${pageContext.request.contextPath}/UserServlet?method=logout">如果您呆的厌倦了，可以点我离开</a>
		</h4>
	</center>

</body>
</html>

　　9.5 错误信息提示页面

<%@ 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=UTF-8">
<title>Insert title here</title>
</head>
<body>
	${msg}
</body>
</html>

　　web.xml的配置文件内容如下：

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" id="WebApp_ID" version="2.5">

	<context-param>
		<param-name>MyTitle</param-name>
		<param-value>javaWeb案例之用户的注册</param-value>
	</context-param>  

  <display-name>Login</display-name>
  <welcome-file-list>
    <welcome-file>index.html</welcome-file>
    <welcome-file>index.htm</welcome-file>
    <welcome-file>index.jsp</welcome-file>
    <welcome-file>default.html</welcome-file>
    <welcome-file>default.htm</welcome-file>
    <welcome-file>default.jsp</welcome-file>
  </welcome-file-list>
  <servlet>
    <description></description>
    <display-name>UserServlet</display-name>
    <servlet-name>UserServlet</servlet-name>
    <servlet-class>cn.javabs.login.controller.UserServlet</servlet-class>
  </servlet>
  <servlet-mapping>
    <servlet-name>UserServlet</servlet-name>
    <url-pattern>/UserServlet</url-pattern>
  </servlet-mapping>
</web-app>

　　最终的页面效果如下所示：

原文地址：https://www.cnblogs.com/xiaoxiao5016/p/9746529.html