HTML
1 <!DOCTYPE html> 2 <html lang="zh-CN"> 3 <head> 4 <meta charset="UTF-8" /> 5 <meta name="viewport" content="width=device-width, initial-scale=1.0" /> 6 <title>用户登录</title> 7 <link rel="stylesheet" href="CSS/login.css" /> 8 </head> 9 <body> 10 <form name="user" action="LoginServlet" method="post"> 11 <div class="login"> 12 <h2>用户登录</h2> 13 <div class="login_box"> 14 <input type="text" name="uid" id="uid" autocomplete="off"/><label>用户名</label> 15 </div> 16 <div class="login_box"> 17 <input type="password" name="password" id="password" autocomplete="off"/><label>密码</label> 18 </div> 19 <a href="#" onclick="document.user.submit();return false"> 20 登录 21 <span></span> 22 <span></span> 23 <span></span> 24 <span></span> 25 </a> 26 </div> 27 </form> 28 </body> 29 </html>
CSS
* { /* 初始化 清除页面元素的内外边距 */ padding: 0; margin: 0; /* 盒子模型 */ box-sizing: border-box; } body { /* 弹性布局 让页面元素垂直+水平居中 */ display: flex; justify-content: center; align-items: center; /* 让页面始终占浏览器可视区域总高度 */ height: 100vh; /* 背景渐变色 */ background: linear-gradient(#141e30, #243b55); } .login { /* 弹性布局 让子元素称为弹性项目 */ display: flex; /* 让弹性项目垂直排列 原理是改变弹性盒子的主轴方向 父元素就是弹性盒子 现在改变后的主轴方向是向下了 */ flex-direction: column; /* 让弹性项目在交叉轴方向水平居中 现在主轴的方向是向下 交叉轴的方向是与主轴垂直 交叉轴的方向是向右 */ align-items: center; width: 400px; padding: 40px; background-color: rgba(0, 0, 0, 0.2); box-shadow: 0 15px 25px rgba(0, 0, 0, 0.4); } .login h2 { color: #fff; margin-bottom: 30px; } .login .login_box { /* 相对定位 */ position: relative; width: 100%; } .login .login_box input { /* 清除input框自带的边框和轮廓 */ outline: none; border: none; width: 100%; padding: 10px 0; margin-bottom: 30px; color: #fff; font-size: 16px; border-bottom: 1px solid #fff; /* 背景颜色为透明色 */ background-color: transparent; } .login .login_box label { position: absolute; top: 0; left: 0; padding: 10px 0; color: #fff; /* 这个属性的默认值是auto 默认是这个元素可以被点击 但是如果我们写了none 就是这个元素不能被点击 , 就好像它可见但是不能用 可望而不可即 */ /* 这个就是两者的区别 */ pointer-events: none; /* 加个过渡 */ transition: all 0.5s; } /* :focus 选择器是当input获得焦点是触发的样式 + 是相邻兄弟选择器 去找与input相邻的兄弟label */ /* :valid 选择器是判断input框的内容是否合法,如果合法会执行下面的属性代码,不合法就不会执行,我们刚开始写布局的时候给input框写了required 我们删掉看对比 当没有required的话input框的值就会被认为一直合法,所以一直都是下方的样式 ,但是密码不会,密码框内的值为空,那么这句话局不合法,required不能为空 当我们给密码框写点东西的时候才会执行以下代码*/ .login .login_box input:focus + label, .login .login_box input:valid + label { top: -20px; color: #03e9f4; font-size: 12px; } .login a { overflow: hidden; position: relative; padding: 10px 20px; color: #03e9f4; /* 取消a表现原有的下划线 */ text-decoration: none; /* 同样加个过渡 */ transition: all 0.5s; } .login a:hover { color: #fff; border-radius: 5px; background-color: #03e9f4; box-shadow: 0 0 5px #03e9f4, 0 0 25px #03e9f4, 0 0 50px #03e9f4, 0 0 100px #03e9f4; } .login a span { position: absolute; } .login a span:first-child { top: 0; left: -100%; width: 100%; height: 2px; /* to right 就是往右边 下面的同理 */ background: linear-gradient(to right, transparent, #03e9f4); /* 动画 名称 时长 linear是匀速运动 infinite是无限次运动 */ animation: move1 1s linear infinite; } .login a span:nth-child(2) { right: 0; top: -100%; width: 2px; height: 100%; background: linear-gradient(transparent, #03e9f4); /* 这里多了个0.25s其实是延迟时间 */ animation: move2 1s linear 0.25s infinite; } .login a span:nth-child(3) { right: -100%; bottom: 0; width: 100%; height: 2px; background: linear-gradient(to left, transparent, #03e9f4); animation: move3 1s linear 0.5s infinite; } .login a span:last-child { left: 0; bottom: -100%; width: 2px; height: 100%; background: linear-gradient(#03e9f4, transparent); animation: move4 1s linear 0.75s infinite; } @keyframes move1 { 0% { left: -100%; } 50%, 100% { left: 100%; } } @keyframes move2 { 0% { top: -100%; } 50%, 100% { top: 100%; } } @keyframes move3 { 0% { right: -100%; } 50%, 100% { right: 100%; } } @keyframes move4 { 0% { bottom: -100%; } 50%, 100% { bottom: 100%; } }
LoginServlet
package servlet; import java.io.IOException; import java.sql.Connection; import java.sql.DriverManager; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.text.SimpleDateFormat; import java.util.Date; import javax.servlet.ServletException; import javax.servlet.ServletRequest; import javax.servlet.annotation.WebServlet; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; /** * Servlet implementation class UserServlet */ @WebServlet("/LoginServlet") public class LoginServlet extends HttpServlet { private static final long serialVersionUID = 1L; /** * @see HttpServlet#HttpServlet() */ public LoginServlet() { super(); // TODO Auto-generated constructor stub } /** * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response) */ protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { // TODO Auto-generated method stub } /** * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response) */ protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { // TODO Auto-generated method stub response.setContentType("text/html;charset=UTF-8"); request.setCharacterEncoding("UTF-8"); response.setCharacterEncoding("UTF-8"); SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss"); String date=sdf.format(new Date()); String uid=String.valueOf(request.getParameter("uid")); String pass=String.valueOf(request.getParameter("password")); try { Class.forName("com.mysql.cj.jdbc.Driver"); String url="jdbc:mysql://localhost:3306/family income and expenditure?&useSSL=false&serverTimezone=UTC"; String username="root"; String password=""; Connection conn=DriverManager.getConnection(url,username,password); String sql="select * from user_info where uid='"+uid+"'and password='"+pass+"'"; PreparedStatement ps=conn.prepareStatement(sql); ResultSet rs=ps.executeQuery(); if(rs.next()) { System.out.println(date+" "+uid+" "+"login"); System.out.println(); request.setAttribute("uid", uid); request.getRequestDispatcher("index.html").forward(request,response);//登录成功 }else{ response.getWriter().write("<font style='color:red;font-size:35px'><div align='center'>"+ "用户名或密码错误！5秒后自动跳转"+"</div>"+"</font>"); response.getWriter().write("<div align='center'>" +"如果没有发生跳转，请点"+"<a href='login.html'>"+"这里"+"</div>"); response.setHeader("refresh", "5;url=login.html");//登录失败，重新登录 } }catch(Exception e) { e.printStackTrace(); }finally{ } } }
