JavaWeb 08_JSP+Dao+Bean+Servlet 实现登录注册（连接数据库，验证码登录，两周内免登陆等功能）
一.数据库db_01 表usert 字段username，password
二. 目录
三. 配置信息
四. 代码
index.jsp
<script type="text/javascript"> function refresh() { src="index.jsp?id="+Math.random(); } </script> <%@ page contentType="charset=UTF-8" language="java" import ="java.awt.*" import ="java.awt.image.BufferedImage" import="java.util.*" import="javax.imageio.ImageIO" pageEncoding="gb2312" %> <% response.setHeader("Cache-Control","no-cache"); //在内存中创建图像 int width=60,height=20; BufferedImage image=new BufferedImage(width,height,BufferedImage.TYPE_INT_RGB); //获取画笔 Graphics g=image.getGraphics(); //设置背景色 g.setColor(new Color(200,200,200)); g.fillRect(0,0,width,height); //取随机产生的验证码(4位数字) Random rnd=new Random(); int randNum=rnd.nextInt(8999)+1000; String randStr=String.valueOf(randNum); //将验证码存入session session.setAttribute("randStr",randStr); //将验证码显示到图像中 g.setColor(Color.black); g.setFont(new Font("", Font.PLAIN,20)); g.drawString(randStr,10,17); //随机产生100个干扰点，使图像中的验证码不易被其他程序探测到 for (int i = 0; i < 100; i++) { int x=rnd.nextInt(width); int y=rnd.nextInt(height); g.drawOval(x,y,1,1); } //输出图像到页面 ImageIO.write(image,"JPEG",response.getOutputStream()); out.clear(); out=pageContext.pushBody(); %>
LoginServlet.jsp
<%@ page import="java.net.URLEncoder" %> <%@ page contentType="text/html;charset=UTF-8" pageEncoding="utf-8" language="java" %> <html> <head> <title>LoginServlet</title> </head> <body> <script type="text/javascript"> function validate() { if(login.username1.value===""){ alert("账号不能为空"); return; } if(login.passwd.value===""){ alert("密码不能为空"); return; } if(login.code.value===""){ alert("请输入正确的验证码"); return; } login.submit(); } function refresh() { login.imgValidate.src="index.jsp?id="+Math.random(); } </script> <form name="login" action="/LoginCl" method="post"> 用户名:<input type="text" name="username1"><br> 密码：<input type="password" name="passwd"><br> <input type="checkbox" name="keep" >两周内免登陆<br> 验证码：<input type="text" name="code" size=10> <%--点击图片可进行验证码刷新--%> <img name="imgValidate" src = "index.jsp" onclick="refresh()" ><br> <input type="button" value="登录" onclick="validate()"> <% String username = null; String password = null; Cookie[] cookies = request.getCookies(); for (int i = 0; i < cookies.length; i++) { if ("username".equals(cookies[i].getName())) { username = cookies[i].getValue(); } else if ("password".equals(cookies[i].getName())) { password = cookies[i].getValue(); } } if (username != null && password != null) { response.sendRedirect("welcome.jsp?uname=" +URLEncoder.encode(username,"utf-8")+ "&password=" + password); } %> </form> <form action="register.jsp" method="post"> <input type="submit" value="注册"> </form> </body> </html>
register.jsp
<%@ page language="java" pageEncoding="gb2312" %> <html> <head> <title>register</title> </head> <body> <h1>欢迎您进行注册</h1> <script language="JavaScript" type="text/javascript"> function checkPassword() { var ps=/^[A-Za-z0-9]{6,20}$/; if (!ps.exec(register.password1.value)) { alert("密码必须同时包含大小写字母和数字且长度应该在6-20之间"); return; } register.submit(); } </script> <form name="register" action="registerMessage.jsp" method="post"> 请输入账号：<input type="text" name="name"><br> 请输入密码: <input type="password" name="password1">(要求：必须包含大小写英文和数字无非法字符，长度大于6位小于20位)<br> 请选择性别：<input name="sex" type="radio" value="男" checked>男 <input name="sex" type="radio" value="女" >女<br> 请选择家乡：<select name="home" > <option value="北京">北京</option> <option value="上海">上海</option> <option value="江西">江西</option> </select> <br> 请选择您的爱好：<input name="fav" type="checkbox" value="唱歌">唱歌 <input name="fav" type="checkbox" value="跳舞">跳舞 <input name="fav" type="checkbox" value="打球">打球 <input name="fav" type="checkbox" value="玩游戏">玩游戏<br> <input type="button" value="注册" onclick="checkPassword()"> </form> </body> </html>
registerMessage.jsp
<%@ page import="java.sql.*" %> <%@ page import="login.Dao.UserDao" %> <%@ page language="java" pageEncoding="gb2312" %> <html> <head> <title>message</title> </head> <body> <h2>信息注册成功!该用户注册信息如下：</h2> <% request.setCharacterEncoding("gb2312"); String name=request.getParameter("name"); String password=request.getParameter("password1"); String sex = request.getParameter("sex"); String home = request.getParameter("home"); out.println("账号："+name); out.println("密码："+password); out.println("性别："+sex); out.println("家乡："+home); out.println("兴趣爱好："); String[] fav = request.getParameterValues("fav"); for (int i = 0; i < fav.length; i++) { out.print(fav[i]+" "); } try { UserDao userDao=new UserDao(); userDao.insertUser(name,password); out.println("<br> <a href=LoginServlet.jsp>信息注册成功，点击此处进行登录</a>"); } catch (SQLException e) { e.printStackTrace(); } %> </body> </html>
Bean层：
Counter.java
package login.Bean; public class Counter { private int count=1; public Counter(){} public int getCount() { return count++; } public void setCount(int count) { this.count = count; } }
user.java
package login.Bean; public class User { private String name; private String pd; public User(){} public String getPd() { return pd; } public void setPd(String pd) { this.pd = pd; } public String getName() { return name; } public void setName(String name) { this.name = name; } }
Dao层：
UserDao.java
package login.Dao; import java.sql.*; import java.util.ArrayList; public class UserDao { public boolean SearchUser(String u,String p) throws SQLException { PreparedStatement preparedStatement = null; ResultSet rs =null; Connection con = null; //启动mysql驱动器 try { Class.forName("com.mysql.cj.jdbc.Driver"); con = DriverManager.getConnection("jdbc:mysql://localhost:3306/db_01?useUnicode=true&characterEncoding=utf-8", "root", "root"); String sql = "select * from usert where username=? and password=?"; preparedStatement = con.prepareStatement(sql); preparedStatement.setString(1, u); preparedStatement.setString(2, p); rs = preparedStatement.executeQuery(); if(rs.next()){ return true; } else { return false; } } catch (ClassNotFoundException e) { e.printStackTrace(); } catch (SQLException e) { e.printStackTrace(); } finally { if(rs!=null) { rs.close(); } if(preparedStatement!=null) { preparedStatement.close(); } if(con!=null){ System.out.println("数据库连接成功！"); con.close(); } } return false; } public void insertUser(String u,String p) throws SQLException { ArrayList users=new ArrayList(); PreparedStatement preparedStatement = null; Connection con = null; //启动mysql驱动器 try { Class.forName("com.mysql.cj.jdbc.Driver"); con = DriverManager.getConnection("jdbc:mysql://localhost:3306/db_01?useUnicode=true&characterEncoding=utf-8", "root", "root"); preparedStatement = con.prepareStatement("insert into usert values(?,?)"); preparedStatement.setString(1,u); preparedStatement.setString(2,p); preparedStatement.executeUpdate(); } catch (ClassNotFoundException e) { e.printStackTrace(); } catch (SQLException e) { e.printStackTrace(); } finally { if(con!=null) { con.close(); } if(preparedStatement!=null) { preparedStatement.close(); } } } }
Register层：
LoginCl.java (servlet)
import javax.servlet.*; import javax.servlet.http.*; import javax.servlet.annotation.*; import java.io.IOException; import java.net.URLEncoder; import java.sql.SQLException; @WebServlet(name = "LoginCl", value = "/LoginCl") public class LoginCl extends HttpServlet { @Override protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { //中文乱码解决方法 response.setContentType("text/html;charset=utf-8"); request.setCharacterEncoding("utf-8"); //防止非法登录 得到session HttpSession httpSession = request.getSession(true); //修改session的存在时间为20s httpSession.setMaxInactiveInterval(20); httpSession.setAttribute("pass", "ok"); //获取用户名的账号和密码 String u = null; //针对jsp 其username为username1 u = request.getParameter("username1"); String p = null; p = request.getParameter("passwd"); //得到提交的验证码 String code = request.getParameter("code"); //获取session验证码 HttpSession session = request.getSession(); String randStr = (String) session.getAttribute("randStr"); //获取到 if (code.equals(randStr)) { //访问数据库 UserDao userDao=new UserDao(); try { if (!userDao.SearchUser(u,p)) { response.getWriter().println("<a href=LoginServlet.jsp>抱歉：账号或密码错误，请注意核实信息重新输入</a>"); return; } else { String keep = request.getParameter("keep"); if (keep != null) { //创建cookie Cookie cookie1 = new Cookie("username", u); Cookie cookie2 = new Cookie("password", p); //设置关联路径 cookie1.setPath(request.getContextPath()); cookie2.setPath(request.getContextPath()); //设置cookie的消亡时间 两周 cookie1.setMaxAge(2 * 7 * 24 * 60 * 60); cookie1.setMaxAge(2 * 7 * 24 * 60 * 60); //把cookie信息写给浏览器 response.addCookie(cookie1); response.addCookie(cookie2); } response.sendRedirect("welcome.jsp?uname=" + URLEncoder.encode(u, "utf-8") + "&password=" + p); } } catch (SQLException e) { e.printStackTrace(); } } } @Override protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { this.doGet(request,response); } }
web.xml
welcom.jsp
<%@ page import="java.util.Date" %> <%@ page contentType="text/html;charset=gb2312" pageEncoding="gb2312" language="java" import="login.Bean.*" %> <%@ page import="java.net.URLDecoder" %> <html> <head> <title>welcome</title> </head> <body> <% request.setCharacterEncoding("gb2312"); HttpSession httpSession=request.getSession(true); String val=(String)httpSession.getAttribute("pass"); if(val==null){ response.sendRedirect("LoginServlet.jsp"); } int counter=0; application.setAttribute("COUNTER",new Integer(counter)); %> <jsp:useBean id="mycount" class="login.Bean.Counter" scope="session"/> <jsp:useBean id="user" class="login.Bean.User" scope="session"> <jsp:setProperty name="user" property="name" param="uname"/> <jsp:setProperty name="user" property="pd" param="password"/> </jsp:useBean> <h1>主界面</h1> <%--welcome name =<%=u%> password =<%=p%><br>--%> <%--welcome name :<jsp:getProperty name="user" property="name" />--%> welcome name : <% out.println(URLDecoder.decode(user.getName(),"utf-8")); %> password:<jsp:getProperty name="user" property="pd" /><br> <%--welcome name :<%out.println(session.getAttribute("username"));%> password:<%out.println(session.getAttribute("password"));%><br>--%> <%--这是你第:<%=counter%>次访问本网站!<br>--%> 这是你第:<jsp:getProperty name="mycount" property="count"/> 次访问本网站!<br> <a href='LoginServlet.jsp'>返回重新登录</a><br> <% Cookie[] cookies = request.getCookies(); if(cookies!=null) { for (int i = 0; i < cookies.length; i++) { if (cookies[i].getName().equals("lastAccessTime")) { out.println("您上次访问的时间是："); Long lastAccessTime = Long.parseLong(cookies[i].getValue()); Date date = new Date(lastAccessTime); out.println(date.toLocaleString()); } } }
//用户访问过后重新设置用户的访问时间，存储在cookie中，然后发送到客户端浏览器 Cookie cookie=new Cookie("lastAccessTime",System.currentTimeMillis()+""); //设置cookie的有效期为5min cookie.setMaxAge(300); //将cookie对象添加到response对象中，这样服务器在输出response对象中的内容时 // 就会把cookie也输入到客户端浏览器 response.addCookie(cookie); %> </body> </html>
五. 效果
输入登录信息之后：
数据库信息：
