<%@ page language="java" import="java.util.*" pageEncoding="UTF-8" session="true"%> <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> <title>登录</title> </head> <body> sessionID<%=session.getId() %> <% Object username=session.getAttribute("username"); if(username==null){ username=""; } %> <form action="hello.jsp" method="post"> username:<input type="text" name="username" value="<%= username %>"/> <input type="submit" value="Submit"/> </form> </body> </html>
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8" session="true"%> <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> <title>HELLO SESSION</title> </head> <body> sessionID<%=session.getId() %> <%=request.getParameter("username") %> <% session.setAttribute("username", request.getParameter("username")); %> <a href="<%= response.encodeURL("login.jsp") %>">重新登录</a> <a href="<%= response.encodeURL("zhuxiao.jsp") %>">注销</a> </body> </html>
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8" session="true"%> <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> <title>注销</title> </head> <body> sessionId:<%=session.getId() %> <h3>Session</h3> Bye: <%= session.getAttribute("username") %> <% session.invalidate(); %> </body> </html>
在servlet中：存入到session中 :session.setAttribute("username", request.getParameter("username"));
在页面中取值：session.getAttribute("username")
当浏览器禁用了cookie后，就可以用URL重写这种解决方案解决Session数据共享问题。而且response. encodeRedirectURL(java.lang.String url) 和response. encodeURL(java.lang.String url)是两个非常智能的方法，当检测到浏览器没有禁用cookie时，那么就不进行URL重写了。