javaweb用户注册登录页面练习--只实现添加功能

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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>

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Java教程

javaweb用户注册登录页面练习--只实现添加功能

项目设计流程

业务流程

数据库创建

项目目录结构

实体类

UserModel

Dao

UserDao

业务逻辑层

UserService

控制层

UserServlet

AuthCodeServlet

前端页面

reg注册

login登录界面

success注册成功界面

list列表界面

add添加界面

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后端开发

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区块链

游戏开发

网站运营

大数据/云计算

软件工程

软件/开发工具使用

资讯