【任务目标】

按照JSP Model2思想编写一个用户注册程序。

组件关系图如下:

(1)UserBean: 封装用户信息的JavaBean。
(2)RegisterFormBean是封装注册表单信息的JavaBeanl,用于校验从ControllerServlet中获取到的注册表单信息中的各个属性
(3)DBUtil是用于访问数据库的辅助类
(4)ControllerServlet是控制器,它负责处理用户注册的请求,如果注册成功,就会跳转到loginSuccess.jsp页面,如果注册失败,则重新跳转回到register.jsp
(5)register.jsp是用户注册表单页面,交给ControllerServlet处理
(6)loginSuccess.jsp是用户登录成功后进入的页面

代码下载地址(访问密码: 7331):jspModel2(用户注册模型).zip: https://url47.ctfile.com/f/64055047-1504966381-3d3137?p=7331

1、创建项目

参考这篇文章

IDEA(2020版)实现Servlet程序 – 每天进步一点点

创建一个Servlet空白模板(项目名称为jspModel2)

创建完项目后,右击src文件夹,选择New—>Package

包名假定为com.demo08

在demo08文件夹底下再创建两个文件夹,一个叫domain、一个叫util

生成后项目结构如下:

2、编写JavaBean

右击domain文件夹,选择New—>Java Class,名字为UserBean

UserBean的参考代码如下:

public class UserBean {
    private String name;            //定义用户名
    private String password;       //定义密码
    private String email;           //定义邮箱
    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;
    }
    public String getEmail() {
        return email;
    }
    public void setEmail(String email) {
        this.email = email;
    }
}
3、编写RegisterFormBean类

右击domain文件夹,选择New—>Java Class,名字为RegisterFormBean

代码参考如下:

package com.demo08.domain;

import java.util.HashMap;
import java.util.Map;

public class RegisterFormBean {
    private String name;            //定义用户名
    private String password;       //定义密码
    private String password2;      //定义确认密码
    private String email;           //定义邮箱
    // 定义成员变量errors,用于封装表单验证时的错误信息
    private Map<String, String> errors = new HashMap<String, String>();
    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;
    }
    public String getPassword2() {
        return password2;
    }
    public void setPassword2(String password2) {
        this.password2 = password2;
    }
    public String getEmail() {
        return email;
    }
    public void setEmail(String email) {
        this.email = email;
    }
    public boolean validate() {
        boolean flag = true;
        if (name == null || name.trim().equals("")) {
            errors.put("name", "请输入姓名.");
            flag = false;
        }
        if (password == null || password.trim().equals("")) {
            errors.put("password", "请输入密码.");
            flag = false;
        } else if (password.length() > 12 || password.length() < 6) {
            errors.put("password", "请输入6-12个字符.");
            flag = false;
        }
        if (password != null && !password.equals(password2)) {
            errors.put("password2", "两次输入的密码不匹配.");
            flag = false;
        }
        // 对email格式的校验采用了正则表达式
        if (email == null || email.trim().equals("")) {
            errors.put("email", "请输入邮箱.");
            flag = false;
        } else if (!email
                .matches("[a-zA-Z0-9_-]+@[a-zA-Z0-9_-]+(\\.[a-zA-Z0-9_-]+)+")) {
            errors.put("email", "邮箱格式错误.");
            flag = false;
        }
        return flag;
    }
    // 向Map集合errors中添加错误信息
    public void setErrorMsg(String err, String errMsg) {
        if ((err != null) && (errMsg != null)) {
            errors.put(err, errMsg);
        }
    }
    // 获取errors集合
    public Map<String, String> getErrors() {
        return errors;
    }
}
4、创建工具类DBUtil

右击util文件夹,选择New—>Java Class,名字为DBUtil, 主要用来模拟数据库操作。

代码参考如下:

package com.demo08.util;

import com.demo08.domain.UserBean;

import java.util.HashMap;

public class DBUtil {
    private static DBUtil instance = new DBUtil();
    // 定义users集合,用于模拟数据库
    private HashMap<String,UserBean> users = new HashMap<String,UserBean>();
    private DBUtil() {
        // 向数据库(users)中存入两条数据
        UserBean user1 = new UserBean();
        user1.setName("Jack");
        user1.setPassword("12345678");
        user1.setEmail("jack@it315.org");
        users.put("Jack ",user1);
        UserBean user2 = new UserBean();
        user2.setName("Rose");
        user2.setPassword("abcdefg");
        user2.setEmail("rose@it315.org");
        users.put("Rose ",user2);
    }
    public static DBUtil getInstance()	{
        return instance;
    }
    // 获取数据库(users)中的数据
    public UserBean getUser(String userName) {
        UserBean user = (UserBean) users.get(userName);
        return user;
    }
    // 向数据库(users)插入数据
    public boolean insertUser(UserBean user) {
        if(user == null) {
            return false;
        }
        String userName = user.getName();
        if(users.get(userName) != null) {
            return false;
        }
        users.put(userName,user);
        return true;
    }
}
5、创建Servlet

主要用来接收用户的请求信息,拿到用户的用户名和密码,然后进行校验。

右击demo08文件夹,选择New—>Package,文件夹的名字为web

继续右击刚才创建的web文件夹,选择New—>Create New Servlet

名字为ControllerServlet

代码参考如下:

package com.demo08.web;

import com.demo08.domain.RegisterFormBean;
import com.demo08.domain.UserBean;
import com.demo08.util.DBUtil;

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;

@WebServlet(name = "ControllerServlet", urlPatterns =
        "/ControllerServlet")
public class ControllerServlet extends HttpServlet {
    public void doGet(HttpServletRequest request,
                      HttpServletResponse response) throws ServletException, IOException {
        this.doPost(request, response);
    }
    public void doPost(HttpServletRequest request,
                       HttpServletResponse response) throws ServletException, IOException {
        response.setHeader("Content-type", "text/html;charset=GBK");
        response.setCharacterEncoding("GBK");
        // 获取用户注册时表单提交的参数信息
        String name = request.getParameter("name");
        String password=request.getParameter("password");
        String password2=request.getParameter("password2");
        String email=request.getParameter("email");
        // 将获取的参数封装到注册表单相关的RegisterFormBean类中
        RegisterFormBean formBean = new RegisterFormBean();
        formBean.setName(name);
        formBean.setPassword(password);
        formBean.setPassword2(password2);
        formBean.setEmail(email);
        // 验证参数填写是否符合要求,如果不符合,转发到register.jsp重新填写
        if(!formBean.validate()){
            request.setAttribute("formBean", formBean);
            request.getRequestDispatcher("/register.jsp")
                    .forward(request, response);
            return;
        }
        // 参数填写符合要求,则将数据封装到UserBean类中
        UserBean userBean = new UserBean();
        userBean.setName(name);
        userBean.setPassword(password);
        userBean.setEmail(email);
        // 调用DBUtil类中的insertUser()方法执行添加操作,并返回一个boolean类型的标志
        boolean b = DBUtil.getInstance().insertUser(userBean);
        // 如果返回为false,表示注册的用户已存在,则重定向到register.jsp重新填写
        if(!b){
            request.setAttribute("DBMes", "你注册的用户已存在");
            request.setAttribute("formBean", formBean);
            request.getRequestDispatcher("/register.jsp")
                    .forward(request, response);
            return;
        }
        response.getWriter().print("恭喜你注册成功,3秒钟自动跳转");
        // 将成功注册的用户信息添加到Session中
        request.getSession().setAttribute("userBean", userBean);
        // 注册成功后,3秒跳转到登录成功页面loginSuccess.jsp
        response.setHeader("refresh","3;url=loginSuccess.jsp");
    }
}
6、创建注册界面register.jsp

右击底部的web文件夹,选择New—>JSP/JSPX

这里jsp文件的名字就叫register

参考代码如下:


<%@ page language="java" pageEncoding="GBK"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01
Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
    <title>用户注册</title>
    <style type="text/css">
        h3 {
            margin-left: 100px;
        }zhuc
         #outer {
             width: 750px;
         }
        span {
            color: #ff0000
        }
        div {
            height:20px;
            margin-bottom: 10px;
        }
        .ch {
            width: 80px;
            text-align: right;
            float: left;
        }
        .ip {
            width: 500px;
            float: left
        }
        .ip>input {
            margin-right: 20px
        }
        #bt {
            margin-left: 50px;
        }
        #bt>input {
            margin-right: 30px;
        }
    </style>
</head>
<body>
<form action="/demo8/ControllerServlet" method="post">
    <h3>用户注册</h3>
    <div id="outer">
        <div>
            <div class="ch">姓名:</div>
            <div class="ip">
                <input type="text" name="name" value="${formBean.name }" />
                <span>${formBean.errors.name}${DBMes}</span>
            </div>
        </div>
        <div>
            <div class="ch">密码:</div>
            <div class="ip">
                <input type="text" name="password">
                <span>${formBean.errors.password}</span>
            </div>
        </div>
        <div>
            <div class="ch">确认密码:</div>
            <div class="ip">
                <input type="text" name="password2">
                <span>${formBean.errors.password2}</span>
            </div>
        </div>
        <div>
            <div class="ch">邮箱:</div>
            <div class="ip">
                <input type="text" name="email" value="${formBean.email }" >
                <span>${formBean.errors.email}</span>
            </div>
        </div>
        <div id="bt">
            <input type="reset" value="重置 " />
            <input type="submit" value="注册" />
        </div>
    </div>
</form>
</body>
</html>
        
7、编程loginSuccess.jsp文件

这个文件表示用户登录成功的显示界面

右击底部的web文件夹,选择New—>JSP/JSPX

这里jsp文件的名字就叫loginSucces

参考代码如下:

<%@ page language=”java” pageEncoding=”GBK”
import=”com.tom.domain.UserBean”%>
<!DOCTYPE html PUBLIC “-//W3C//DTD HTML 4.01
Transitional//EN” “http://www.w3.org/TR/html4/loose.dtd”>
<html>
<head>
<title>login successfully</title>
<style type=”text/css”>
#main {
width: 500px;
height: auto;
}
#main div {
width: 200px;
height: auto;
}
ul {
padding-top: 1px;
padding-left: 1px;
list-style: none;
}
</style>
</head>
<body>
<%
if (session.getAttribute(“userBean”) == null) {
%>
<jsp:forward page=”register.jsp” />
<%
return;
}
%>
<div id=”main”>
<div id=”welcome”>恭喜你,登录成功</div>
<hr />
<div>您的信息</div>
<div>
<ul>
<li>您的姓名:${userBean.name }</li>
<li>您的邮箱:${userBean.email }</li>
</ul>
</div>
</div>
</body>
</html>

8、运行结果