从页面a.jsp跳传到页面b.jsp
（a页传参给b页面）
利用session传参
a.jsp页面如下：
--------------------------
<%@ page language="java" pageEncoding="UTF-8"%>
<jsp:directive.page import="javax.servlet.http.HttpSession"/>
<%
HttpSession newsession = request.getSession();
newsession.setAttribute("Adduser","adduser");
%>
<html>
</html>
b.jsp页面如下：
--------------------------
<%@ page language="java" pageEncoding="UTF-8"%>
<jsp:directive.page import="javax.servlet.http.HttpSession"/>
<%
HttpSession newsession = request.getSession();
String typeid=(String)newsession.getAttribute("Adduser");
if(typeid==null){
response.sendRedirect("welcome.jsp");
}
%>
<html>
</html>