ICode9
精准搜索请尝试： 精确搜索
首页
编程语言>
数据库
系统相关
互联网
其他分享
Python
Java
JavaScript
android
PHP
首页 > 编程语言> 文章详细

javaweb用户注册登录页面练习--只实现添加功能

2022-01-14 16:33:58  阅读：197  来源： 互联网

标签：return String 用户注册 -- req pass import model javaweb


项目设计流程

业务流程

一个业务都是从后到前，首先第一步：设计数据库–dao–service(调用多个dao)–servlet（接受用户请求，做出响应）--------HTML（JSP技术）
table-->model-->dao(jdbc)-->web-->servlet-->service

数据库创建

在这里插入图片描述

项目目录结构

在这里插入图片描述

实体类

UserModel

package com.situ.info.user.model;

public class UserModel {
	
	private Integer id;
	private String username;
	private String pass;
	private String sex;
	private String hobby;
	public Integer getId() {
		return id;
	}
	public void setId(Integer id) {
		this.id = id;
	}
	public String getUsername() {
		return username;
	}
	public void setUsername(String string) {
		this.username = string;
	}
	public String getPass() {
		return pass;
	}
	public void setPass(String pass) {
		this.pass = pass;
	}
	public String getSex() {
		return sex;
	}
	public void setSex(String sex) {
		this.sex = sex;
	}
	public String getHobby() {
		return hobby;
	}
	public void setHobby(String hobby) {
		this.hobby = hobby;
	}
	public String getAddress() {
		return address;
	}
	public void setAddress(String address) {
		this.address = address;
	}
	private String address;

}

Dao

UserDao

package com.situ.info.user.dao;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;

import org.junit.jupiter.api.Test;

import com.situ.info.user.model.UserModel;
import com.situ.info.util.JDBCUtil;

public class UserDao {
	
	public String insert(UserModel model) {
		String sql="insert into user(username,pass,sex,hobby,address)values(?,?,?,?,?)";
		Connection conn = null;// 建立连接，获得连接对象
		PreparedStatement ps = null;// 定义状态集,一般使用预处理的状态集 PreparedStatement
		String res="";
		try {//异常处理推荐使用try catch
			conn = JDBCUtil.getConnection();
			ps = conn.prepareStatement(sql);// 获取状态集
			ps.setString(1, model.getUsername());// 填充状态集数据
			ps.setString(2, model.getPass());
			ps.setString(3, model.getSex());
			ps.setString(4, model.getHobby());
			ps.setString(5, model.getAddress());
			res+=ps.executeUpdate();
		} catch (SQLException e) {
			e.printStackTrace();
		} finally {
			JDBCUtil.close(conn, ps, null);
		}
		return res;//不能省略，前两 个return不一定返回
	}
	
	public String delete(UserModel model) {
		String sql = "delete from student where username =?";
		Connection conn = null;// 建立连接，获得连接对象
		PreparedStatement ps = null;// 定义状态集,一般使用预处理的状态集 PreparedStatement
		String res="";
		try {
			conn = JDBCUtil.getConnection();
			ps = conn.prepareStatement(sql);// 获取状态集
			ps.setString(1, model.getUsername());// 填充状态集数据
			res+=ps.executeUpdate();
		} catch (SQLException e) {
			e.printStackTrace();
		} finally {
			JDBCUtil.close(conn, ps, null);
		}
		return res;
	}
	
	public String update(UserModel model) {
		String sql="upsete student set username=?,pass=?,sex=?,hobby=?,address=? ";
		Connection conn = null;// 建立连接，获得连接对象
		PreparedStatement ps = null;// 定义状态集,一般使用预处理的状态集 PreparedStatement
		String res="";
		try {
			conn = JDBCUtil.getConnection();
			ps = conn.prepareStatement(sql);// 获取状态集
			ps.setString(1, model.getUsername());// 填充状态集数据
			ps.setString(2, model.getPass());
			ps.setString(3, model.getSex());
			ps.setString(4, model.getHobby());
			ps.setString(5, model.getAddress());
			res+=ps.executeUpdate();
		} catch (SQLException e) {
			e.printStackTrace();
		} finally {
			JDBCUtil.close(conn, ps, null);
		}
		return res;	
	}
	
	
	public List<UserModel> selectList(UserModel model) {
		StringBuffer sql=new StringBuffer("select id,username,pass,sex,hobby,address from user where 1=1");
		//where 1=1方便拼接多个and
		List<Object> list=new ArrayList<>();
		String username=model.getUsername();
		if(username != null && !username.isEmpty()) {//判断数据是否存在，---数据不是null或空字符串
			sql.append(" and username=?");
			list.add(username);
		}
		String pass=model.getPass();
		if(pass != null && !pass.isEmpty()) {//判断数据是否存在，---数据不是null或空字符串
			sql.append(" and pass=?");
			list.add(pass);
		}
		Connection conn=null;// 建立连接
		PreparedStatement ps = null; //定义状态集,一般使用预处理的状态集 PreparedStatement
		ResultSet rs = null;//定义结果集
		List<UserModel> result=new ArrayList<>();
		try {
			conn=JDBCUtil.getConnection1();// 获取状态集
			ps = conn.prepareStatement(sql.toString());//stringbuffer类型转换成string类型
			for(int i=0;i<list.size();i++) 
				ps.setObject(i+1, list.get(i));
			rs = ps.executeQuery();//获取结果集
			while(rs.next()) {
				UserModel userModel=new UserModel();
				userModel.setId(rs.getInt("id"));
				userModel.setUsername(rs.getString("username"));
				userModel.setPass(rs.getString("pass"));
				userModel.setSex(rs.getString("sex"));
				userModel.setHobby(rs.getString("hobby"));
				userModel.setAddress(rs.getString("address"));
				result.add(userModel);
			}
		} catch (SQLException e) {
			e.printStackTrace();
		}finally {
			JDBCUtil.close(conn, ps, rs);
		}
		
		return result;
	}
}

业务逻辑层

UserService

package com.situ.info.user.service;

import java.sql.SQLException;
import java.util.List;

import com.situ.info.user.dao.UserDao;
import com.situ.info.user.model.UserModel;

//业务逻辑层/服务层
public class UserService {//无具体业务逻辑实现
	
	private UserDao dao=new UserDao();
	
	/**
	 * 添加记录，username重复则不允许添加，返回null，否则可以添加，返回影响记录条数
	 * @param model
	 * @return String
	 */
	public String insert(UserModel model) {
		UserModel m1=new UserModel();
		m1.setUsername(model.getUsername());
		List<UserModel> list = dao.selectList(m1);
		if(list.isEmpty()) 
			return dao.insert(model);
		return null;
		
		
	}
	
	public String delete(UserModel model) {
		return dao.delete(model);
	}
	
	public String update(UserModel model) {
		return dao.update(model);
	}

	public List<UserModel> selectList(UserModel model) {
		return dao.selectList(model);		
	}

	/**
	 * 登录功能，账号存在其密码正确，成功登录
	 * @param model
	 * @return 
	 */
	public UserModel login(UserModel model) {//登录功能，账号和密码
		UserModel m1=new UserModel();
		m1.setUsername(model.getUsername());
		List<UserModel> list = dao.selectList(m1);
		if(list.isEmpty()) {//账号不存在
			m1.setId(-1);
			return m1;
		}
		UserModel mdb = list.get(0);
		if(list.get(0).getPass().equals(model.getPass()))//密码正确，登录成功
			return mdb;
		else {//登录成功
			m1.setId(-2);
			return m1;
		}		
	}
	
}

控制层

UserServlet

package com.situ.info.user.servlet;

import java.io.IOException;
import java.sql.SQLException;
import java.util.List;

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.situ.info.user.model.UserModel;
import com.situ.info.user.service.UserService;
import com.situ.info.util.MD5;

//控制层=接收请求+获取数据+封装对象+调用方法+页面跳转
@WebServlet("/UserServlet")
public class UserServlet extends HttpServlet{

	private static final long serialVersionUID = 1L;
	
	@Override
	protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
		doPost(req,resp);
	}
	
	private UserService service=new UserService();
//			把下一级对应文件对应的变量得到

	@Override
	protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
		req.setCharacterEncoding("UTF-8");
		resp.setCharacterEncoding("UTF-8");
		resp.setContentType("text/html;charset=UTF-8");
		
		String message = null;
		String path=null;
		String back=null;
		String contextPath=req.getContextPath();
		String back1="<a href='"+contextPath+"/web/login.jsp'>返回登录</a>"
				+ "&nbsp;<a href='"+contextPath+"/web/reg.jsp'>返回注册</a>";
		String back2="<a href='"+contextPath+"/UserServlet?action=list'>返回列表</a>";
		String path1="/web/success.jsp";
		String path2="/UserServlet?action=list";
		String path3="/web/list.jsp";
		String action = req.getParameter("action");//得到隐藏域
		switch (action) {//用switch分支和隐藏域完成多个请求请求到一个servlet
		case "add":
			message = add(req);			
			path=path1;
			back=back2;
			break;
		case "reg":
			message = add(req);			
			path=path1;
			back=back1;
			break;
		case "login":
			message=login(req);
			if("登陆成功".equals(message)) {
				path=path2;
			}else {
				path=path1;
				back=back1;
		    }
			break;
		case "list":
			UserModel userModel=new UserModel();
			req.setAttribute("list", service.selectList(userModel));
			path=path3;
			break;
		default:
			break;
		}
		
		req.setAttribute("back", back);
		req.setAttribute("message", message);
		req.getRequestDispatcher(path).forward(req, resp);
	}
	
	private String login(HttpServletRequest req) {//登录成功-用户信息-存到session中
		String username =req.getParameter("username");
		if(username==null||username.isEmpty())//账号为空检验
			return "操作失败，账号不能为空";
		String pass =req.getParameter("pass");
		if(pass==null||pass.isEmpty())//密码为空检验
			return "操作失败，密码不能为空";
		if(!isOKAnthcode(req))//验证码检验
			return "操作失败，验证码错误";
		
		pass=MD5.encode(pass);
		UserModel model = new UserModel();
		model.setUsername(username);
		model.setPass(pass);
		
		UserModel mdb = service.login(model);
		Integer id=mdb.getId();
		if(id==-1) {
			return "账号不存在";
		}
		if(id==-2) {
			return "密码错误";
		}
		req.getSession().setAttribute("user", mdb);
		return "登陆成功";
	}
	
	private boolean isOKAnthcode(HttpServletRequest req) {
		String authcode = req.getParameter("authcode");//取出网页传过来的的验证码
		Object auth_code = req.getSession().getAttribute("auth_code");//得到session中存的验证码
		return auth_code.toString().equals(authcode);
	}

	private String add(HttpServletRequest req) {//往数据库中添加数据，用户注册
		String username =req.getParameter("username");
		if(username==null||username.isEmpty())//账号为空检验
			return "操作失败，账号不能为空";
		String pass =req.getParameter("pass");
		if(pass==null||pass.isEmpty())//密码为空检验
			return "操作失败，密码不能为空";
		if(!isOKAnthcode(req))
			return "操作失败，验证码错误";
		pass=MD5.encode(pass);
		String sex =req.getParameter("sex");
		String[] hobby =req.getParameterValues("hobby");
		StringBuffer hobbystring=new StringBuffer();
		if(hobby!=null&&hobby.length>0) {//判断不为空或空字符串
			hobbystring.append(hobby[0]);
			for(int i=0;i<hobby.length;i++)//拼接字符串
				hobbystring.append(",").append(hobby[i]);
		}
		String address =req.getParameter("address");
		
		
		UserModel model=new UserModel();
		model.setUsername(username);
		model.setPass(pass);
		model.setSex(sex);
		model.setHobby(hobbystring.toString());
		model.setAddress(address);
		
		String result = service.insert(model);
		if(result!=null&&!result.isEmpty()) {
			return "操作成功，账号："+username;
			
		}else
			return "操作失败，账号重复";
	}	
}

AuthCodeServlet

package com.situ.info.user.servlet;

import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics2D;
//awt swing java可视化界面的工具
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.util.Random;

import javax.imageio.ImageIO;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

@WebServlet("/AuthCodeServlet")
public class AuthCodeServlet extends HttpServlet{

	private static final long serialVersionUID = 1L;
	private static char[] chs="1234567890abcdefghijklmnopqrstuiwxyz".toCharArray();
	
	@Override
	protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
		BufferedImage image=new BufferedImage(75,25,BufferedImage.TYPE_INT_RGB);
		Graphics2D g = image.createGraphics();
		g.setColor(new Color(200,200,255));
		g.fillRect(0, 0, 75, 75);
		g.setFont(new Font("隶书", Font.BOLD, 15));
		
		StringBuffer str = new StringBuffer();
		Random r = new Random();
		for(int i=0;i<4;i++) {
			int index=r.nextInt(10);
			g.setColor(new Color(r.nextInt(255),r.nextInt(255),r.nextInt(255)));
			g.drawString(chs[index]+"",15*i+3, 16+(r.nextInt(3)));
			str.append(chs[index]);
		}
		
		req.getSession().setAttribute("auth_code", str.toString());//用Session可以在多变量的情况下使用
		ImageIO.write(image, "jpg", resp.getOutputStream());//以字节流的形式返回到网页上
	}
}

前端页面

reg注册

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Insert title here</title>
</head>
<body>
<!-- http://127.0.0.1:8080/demo220107/web/reg.jsp -->

<!-- <form action="/demo220107/UserServlet"> -->
<%-- <form action="<%=request.getContextPath() %>/UserServlet"> --%>
<form action="${pageContext.request.contextPath }/UserServlet" method="post">
账号<input type="text" name="username" /><br>
密码<input type="password" name="pass" /><br>
性别<input type="radio" name="sex" value="男" />男
<input type="radio" name="sex" value="女" />女<br>
爱好<input type="checkbox" name="hobby" value="跑步" />跑步
<input type="checkbox" name="hobby" value="游泳"/>游泳
<input type="checkbox" name="hobby" value="睡觉"/>睡觉
地址<select name="address">
<option value="北京">北京</option>
<option value="山东">山东</option>
<option value="上海">上海</option>
</select><br>

<img  src="${pageContext.request.contextPath }/AuthCodeServlet" 
onclick="this.src='${pageContext.request.contextPath }/AuthCodeServlet?'+Math.random()">
<input type="text" name="authcode"><br>
<input type="reset">
<input type="submit" value="注册">
<!-- 实现页面跳转 -->
<input type="button" value="跳转登录" onclick="toLogin()">
<!-- 让多个请求请求到同一个servlet，用隐藏域实现 -->
<input type="hidden" name="action" value="reg">
</form>

<script type="text/javascript">
function toLogin() {
	location.href="${pageContext.request.contextPath}/web/login.jsp";//实现页面跳转功能
}
</script>

</body>
</html>

login登录界面

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Insert title here</title>
</head>
<body>
<!-- http://127.0.0.1:8080/demo220107/web/login.jsp -->
<form action="${pageContext.request.contextPath }/UserServlet">
账号<input type="text" name="username" /><br>
密码<input type="password" name="pass" /><br>

<img  src="${pageContext.request.contextPath }/AuthCodeServlet" 
onclick="this.src='${pageContext.request.contextPath }/AuthCodeServlet?'+Math.random()">
<input type="text" name="authcode"><br>
<input type="reset">
<input type="submit" value="登录">
<!-- 实现页面跳转 -->
<input type="button" value="注册" onclick="toReg()">
<!-- 让多个请求请求到同一个servlet，用隐藏域实现 -->
<input type="hidden" name="action" value="login">
</form>

<script type="text/javascript">
function toReg() {
	location.href="${pageContext.request.contextPath}/web/reg.jsp";//实现页面跳转功能
}
</script>


</body>
</html>

success注册成功界面

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
   <%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core"  %>
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Insert title here</title>
</head>
<body>

${message}<br>

<c:out value="${back }" escapeXml="false" />
<%-- <a href="${pageContext.request.contextPath}/web/login.jsp">返回登录</a> --%>
<%-- <a href="${pageContext.request.contextPath}/web/reg.jsp">返回注册</a> --%>

</body>
</html>

list列表界面

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
 <%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Insert title here</title>
</head>
<body>
列表
<form action="">
账号：<input type="text" name="user">
<input type="submit" value="查询">
<input type="button" value="添加" onclick="toAdd()">
</form><br>
<table style="border: 1px solid black;width:90%">
	<thead>
		<tr>
			<td>序号</td><td>账号</td><td>性别</td>
			<td>爱好</td><td>地址</td><td>操作</td>
		</tr>
	</thead>
	<tbody>
		<c:forEach items="${list }" var="l" varStatus="k">
			<tr>
				<td>${k.count }</td>
				<td>${l.username }</td>
				<td>${l.sex }</td>
				<td>${l.hobby }</td>
				<td>${l.address }</td>
				<td>
					<a href="">修改</a>
					<button onclick="">删除</button>
				</td>
			</tr>
		</c:forEach>
	</tbody>
</table>
<script type="text/javascript">
	var contextPath="${pageContext.request.contextPath}";
function toAdd() {
	location.href=contextPath+"/web/add.jsp"
}
</script>
</body>
</html>

add添加界面

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Insert title here</title>
</head>
<body>
<form action="${pageContext.request.contextPath }/UserServlet" method="post">
账号<input type="text" name="username" /><br>
密码<input type="password" name="pass" /><br>
性别<input type="radio" name="sex" value="男" />男
<input type="radio" name="sex" value="女" />女<br>
爱好<input type="checkbox" name="hobby" value="跑步" />跑步
<input type="checkbox" name="hobby" value="游泳"/>游泳
<input type="checkbox" name="hobby" value="睡觉"/>睡觉
地址<select name="address">
<option value="北京">北京</option>
<option value="山东">山东</option>
<option value="上海">上海</option>
</select><br>

<img  src="${pageContext.request.contextPath }/AuthCodeServlet" 
onclick="this.src='${pageContext.request.contextPath }/AuthCodeServlet?'+Math.random()">
<input type="text" name="authcode"><br>
<input type="reset">
<input type="submit" value="添加">
<!-- 实现页面跳转 -->
<input type="button" value="返回列表" onclick="toList()">
<!-- 让多个请求请求到同一个servlet，用隐藏域实现 -->
<input type="hidden" name="action" value="add">
</form>

<script type="text/javascript">
function toList() {
	location.href="${pageContext.request.contextPath}/UserServlet?action=list";//实现页面跳转功能
}
</script>

</body>
</html>

标签：return,String,用户注册,--,req,pass,import,model,javaweb
来源： https://blog.csdn.net/qq_53290615/article/details/122493267

本站声明： 1. iCode9 技术分享网（下文简称本站）提供的所有内容，仅供技术学习、探讨和分享；
2. 关于本站的所有留言、评论、转载及引用，纯属内容发起人的个人观点，与本站观点和立场无关；
3. 关于本站的所有言论和文字，纯属内容发起人的个人观点，与本站观点和立场无关；
4. 本站文章均是网友提供，不完全保证技术分享内容的完整性、准确性、时效性、风险性和版权归属；如您发现该文章侵犯了您的权益，可联系我们第一时间进行删除；
5. 本站为非盈利性的个人网站，所有内容不会用来进行牟利，也不会利用任何形式的广告来间接获益，纯粹是为了广大技术爱好者提供技术内容和技术思想的分享性交流网站。

关于我们 | 联系我们 | 留言反馈

专注分享技术，共同学习，共同进步。侵权联系[81616952@qq.com]

Copyright (C)ICode9.com, All Rights Reserved.

ICode9版权所有