登录界面代码实现
要求
- 一个注册页面(form表单,servlet)
username(文本框)
password:密码(密码框)
passwordYes :再次输入密码(密码框)
hobby(多选框)
sex(单选框)
info(文本域) - servlet处理注册信息
判断两次密码是否相同
相同则跳到成功页面,并且在成功页面显示SeesionID;
不同则注册失败,重定向到注册页面 - 成功页面
显示登陆成功的用户名,密码,爱好,性别和信息;
显示一个注销按钮 - 如果注销后,或者没登录,不能直接进入成功页面,跳转到错误界面
详细步骤
- 首先建立web项目,建包,导相关的jar包,并关联Tomcat。
- 建立:登录成功的success.jsp文件,登录界面的jsp文件register.jsp,错误界面的jsp文件nologin.jsp,登录错误的Servlet文件loginOutServlet.java,登录Servlet文件RegisterServlet.java,并打开web.xml和index.jsp。
- 编辑index.jsp文件
<%--
Created by IntelliJ IDEA.
User: Administrator
Date: 2019/7/16
Time: 8:54
To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
<title>主界面</title>
<style>
div{
margin: 0 auto;
text-align: center;
}
</style>
</head>
<body>
<div>
<h1>HomeWork</h1>
<hr>
<a href="${pageContext.request.contextPath}/register.jsp">点击注册</a>
</div>
</body>
</html>
- 编写register登录网页
<%--
Created by IntelliJ IDEA.
User: Administrator
Date: 2019/7/16
Time: 10:15
To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
<title>register</title>
<%--如果两次密码不相同,关联RegisterServlet中if判断密码是否正确中的else--%>
<script>
var status = '${sessionScope.passwordError}';
if (status == "yes") {
alert("输入信息有误,请重新输入")
}
</script>
</head>
<body>
<h1>欢迎来到注册界面</h1>
<hr> <%--分割线--%>
<div>
<%--form表单--%>
<form action="${pageContext.request.contextPath}/register.do" method="post">
<p>用户名:<input type="text" name="username" required></p>
<p>密码:<input type="password" name="password" required></p>
<p>密码确认:<input type="password" name="confirmPassword" required></p>
<p>性别:
<input type="radio" name="gender" value="male">男
<input type="radio" name="gender" value="female">女
</p>
<p>爱好:
<input type="checkbox" name="hobby" value="oppositeSex">异性
<input type="checkbox" name="hobby" value="dance">舞蹈
<input type="checkbox" name="hobby" value="music">音乐
<input type="checkbox" name="hobby" value="movies">电影
</p>
<p>个人简介:
<textarea name="info"></textarea>
</p>
<p>
<input type="submit" value="提交">
<input type="reset" value="重置">
</p>
</form>
</div>
</body>
</html>
- 编辑登录Servlet(RegisterServlet.java)
package com.li.work;
import javax.servlet.http.HttpSession;
import java.io.IOException;
import java.util.Arrays;
public class RegisterServlet extends javax.servlet.http.HttpServlet {
protected void doPost(javax.servlet.http.HttpServletRequest request, javax.servlet.http.HttpServletResponse response) throws javax.servlet.ServletException, IOException {
doGet(request, response);
}
protected void doGet(javax.servlet.http.HttpServletRequest request, javax.servlet.http.HttpServletResponse response) throws javax.servlet.ServletException, IOException {
request.setCharacterEncoding("UTF-8");//处理乱码问题
response.setCharacterEncoding("UTF-8");//处理乱码问题
//获得用户在register界面提交的数据
String username = request.getParameter("username");
String password = request.getParameter("password");
String confirmPassword = request.getParameter("confirmPassword");
String gender = request.getParameter("gender");
String info = request.getParameter("info");
String[] hobbies = request.getParameterValues("hobby");
//判断密码是否正确
if (password.equals(confirmPassword)){//如果密码相同,重定向到成功界面
HttpSession session = request.getSession();//获取session
session.setAttribute("session_username",username);
session.setAttribute("session_password",password);
session.setAttribute("session_gender",gender);
session.setAttribute("session_info",info);
session.setAttribute("session_hobby", Arrays.toString(hobbies));
response.sendRedirect("success.jsp");//重定向到成功页面
}else {//如果密码不同,通知用户密码输入不一样
request.getSession().setAttribute("passwordError","yes");
response.sendRedirect("register.jsp");//重定向到登陆界面
}
}
}
- 编辑成功web界面(success.jsp)
<%--
Created by IntelliJ IDEA.
User: Administrator
Date: 2019/7/16
Time: 10:12
To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
<title>success</title>
<style>
h1{
margin: 0 auto;
text-align: center;
}
p>span{
font-weight: bold;
}
</style>
<%
HttpSession loginSession = request.getSession();
if (loginSession.getAttribute("session_username")==null){//如果session中的用户名为空
request.getRequestDispatcher("errorpage/nologin.jsp").forward(request,response);//转发至nologin(注册有误)界面
}
%>
</head>
<body>
<h1>注册成功</h1>
<!--显示用户信息,显示内容从RegisterServlet.java中的session中获得-->
<p>
欢迎用户:<span>${sessionScope.session_username}</span>加入本项目<br>
用户名:<span>${sessionScope.session_username}</span><br>
密码:<span>${sessionScope.session_password}</span><br>
性别:<span>${sessionScope.session_gender}</span><br>
爱好:<span>${sessionScope.session_hobby}</span><br>
个人简介:<span>${sessionScope.session_info}</span><br>
</p>
<!--添加注销按钮,用a标签跳转到loginOutServlet中的loginOut.do-->
<p>
<a href="${pageContext.request.contextPath}/loginOut.do">注销</a>
</p>
</body>
</html>
- 编辑注销的Servlet文件(loginOutServlet.java)
package com.li.work;
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 javax.servlet.http.HttpSession;
import java.io.IOException;
@WebServlet(name = "loginOutServlet")
public class loginOutServlet extends HttpServlet {
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
doGet(request,response);
}
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
HttpSession session = request.getSession();//获取session
if (session==null){
response.sendRedirect("index.jsp");
return;
}
//注销session,移除session中的数据
session.removeAttribute("session_username");
session.removeAttribute("session_password");
session.removeAttribute("session_gender");
session.removeAttribute("session_info");
session.removeAttribute("session_hobby");
//删除数据后跳转至success界面
response.sendRedirect("success.jsp");
}
}
- 编辑登录信息有误的nologin界面(nologin.jsp)
<%--
Created by IntelliJ IDEA.
User: Administrator
Date: 2019/7/16
Time: 10:14
To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
<title>NoLoginPage</title>
<style>
div{
margin: 0 auto;
text-align: center;
}
</style>
</head>
<body>
<div>
<h1>找不到信息,未注册或已注销,请点击登录!</h1>
<hr>
<a href="${pageContext.request.contextPath}/register.jsp">点击注册</a>
</div>
</body>
</html>
- 编辑web.xml
<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_4_0.xsd"
version="4.0">
<servlet>
<servlet-name>RegisterServlet</servlet-name>
<servlet-class>com.li.work.RegisterServlet</servlet-class>
</servlet>
<servlet>
<servlet-name>loginServlet</servlet-name>
<servlet-class>com.li.work.loginOutServlet</servlet-class>
</servlet>
<!--========================================================================-->
<servlet-mapping>
<servlet-name>RegisterServlet</servlet-name>
<url-pattern>/register.do</url-pattern>
</servlet-mapping>
<servlet-mapping>
<servlet-name>loginServlet</servlet-name>
<url-pattern>/loginOut.do</url-pattern>
</servlet-mapping>
</web-app>
要重点搞清楚文件和文件之间的关系和关联,具体方法可以用倒推法,一点一点从网页寻找会Servlet的.java文件中。另外要注意链接各个网页时候路径的位置,包不同路径就不同。
本文是简单的登录界面的代码实现,更复杂的部分和思想不再本文考虑范围