jsp的九種對象我簡述之：
page
application
request
response
session
config
out
pagecontext
 
page
<%@page contenttype="text/html; charset=gb2312" language="java" import="java.sql.*" %>

response
<%
  response.setheader("pragma","no-cache"); 
  response.setheader("cache-control","no-cache"); 
  response.setdateheader("expires", 0); 
%>

<%response.sendredirect("login.jsp");%>

session
<%session.invalidate();%>

request/session
<%
 string errmsg = request.getparameter("errmsg");
 request.getsession(true);
 string chk = "false";
 session.putvalue("enter",chk);
%>

out
<%
 if(errmsg != null && errmsg.equals("error1"))
  out.print("你的用戶號還沒有開通!!");
 else if(errmsg != null && errmsg.equals("error2"))
  out.print("您輸入管理員帳號或者密碼不正確!!");
%> 

下面是request對象在java doc中的說明：其他類似