login.jsp:
1 <%@ page language="java" import="java.util.*" contentType="text/html; charset=utf-8"%> 2 <% 3 String path = request.getContextPath(); 4 String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/"; 5 %> 6 7 <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> 8 <html> 9 <head>10 <base href="<%=basePath%>">11 12 <title>用戶登錄</title>13 14 <meta http-equiv="Words" content="keyword1,keyword2,keyword3">18 <meta http-equiv="descrCSS" href="styles.css">21 -->22 23 </head>24 25 <body>26 <h1>用戶登錄</h1>27 <form action="check" method="post">28 <table border="1" width="250px">29 <tr><td>用戶名:</td><td><input type="text" name="userId" /></td></tr>30 <tr><td>密碼:</td><td><input type="password" name="passwd" /></td></tr>31 <tr><td></td><td><input type="submit" value="提交" /></td></tr>32 </table>33 </form>34 </body>35 </html>
welcom.jsp
1 <%@ page language="java" import="java.util.*" contentType="text/html; charset=utf-8"%> 2 <% 3 String path = request.getContextPath(); 4 String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/"; 5 %> 6 7 <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> 8 <html> 9 <head>10 <base href="<%=basePath%>">11 12 <title>My JSP 'welcome.jsp' starting page</title>13 14 <meta http-equiv="pragma" content="no-cache">15 <meta http-equiv="cache-control" content="no-cache">16 <meta http-equiv="expires" content="0"> 17 <meta http-equiv="keywords" content="keyword1,keyword2,keyword3">18 <meta http-equiv="description" content="This is my page"> 19 </head>20 <%21 String user=(String) session.getAttribute("user");22 if(user==null){23 %>24 <jsp:forward page="login.jsp" />25 <%} %>26 <body>27 熱烈歡迎您:<%=user %>28 </body>29 </html>web.xml
1 <?xml version="1.0" encoding="UTF-8"?> 2 <web-app version="2.5" 3 xmlns="http://java.sun.com/xml/ns/javaee" 4 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 5 xsi:schemaLocation="http://java.sun.com/xml/ns/javaee 6 http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"> 7 <display-name></display-name> 8 <welcome-file-list> 9 <welcome-file>index.jsp</welcome-file>10 </welcome-file-list>11 <servlet>12 <servlet-name>CheckUser</servlet-name>13 <servlet-class>servlet.CheckUser</servlet-class>14 </servlet>15 <servlet-mapping>16 <servlet-name>CheckUser</servlet-name>17 <url-pattern>/check</url-pattern>18 </servlet-mapping>19 20 </web-app>
CheckUser.java
1 package servlet; 2 3 import java.io.IOException; 4 5 import javax.servlet.RequestDispatcher; 6 import javax.servlet.ServletException; 7 import javax.servlet.http.HttpServlet; 8 import javax.servlet.http.HttpServletRequest; 9 import javax.servlet.http.HttpServletResponse;10 import javax.servlet.http.HttpSession;11 12 public class CheckUser extends HttpServlet {13 @Override14 protected void doPost(HttpServletRequest request,15 HttpServletResponse response) throws ServletException, IOException {16 request.setCharacterEncoding("UTF-8");17 String userId=request.getParameter("userId");18 String passwd=request.getParameter("passwd");19 20 if(userId!=null&&passwd!=null&&userId.equals("gys")&&passwd.equals("gys")){21 HttpSession session=request.getSession();22 session.setAttribute("user", userId);23 RequestDispatcher dispatcher=request.getRequestDispatcher("/welcome.jsp");24 dispatcher.forward(request, response);25 }26 else{27 RequestDispatcher dispatcher=request.getRequestDispatcher("/login.jsp");28 dispatcher.forward(request, response);29 }30 }31 }新聞熱點
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