使用servletcontent記錄當前登入使用者資訊
第一張jsp
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<%@page import="java.util.Vector"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
</head>
<body>
<form action="a1servlet" method="get">
<input type="text" name="first"/>
<input type="hidden" name="th"value="a"/>
<input type="submit" value="發表"/>
</form>
<br/>
</body>
</html>
第二張
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<%@page import="java.util.Vector"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
<script>
function comm(a){
document.getElementsByName("ifr1").style.display="show";
a.style.display="block";
}
</script>
<style>
body{
width:1000px;
}
.left{
width:50%;
float:left;
}
.right{
width:50%;
float:left;
}
</style>
</head>
<body>
<div class="left">
登陸成功<br/>
當前線上使用者<br/>
<%
//response.setIntHeader("refresh", 5);
ServletContext context=getServletContext();
Vector hab=(Vector)context.getAttribute("body");
for(int i=0;i<hab.size();i++){
<a href="NewFile2.jsp?name=<%=hab.get(i)%>" target="ifr1"><%=hab.get(i) %></a>
<br/>
<%
}
%>
</div>
<div class="right">
<iframe name="ifr1" id="ifr1" width="50%" align="top" scrolling="no" frameborder="0">
</iframe>
</div>
</body>
servlet操作類·
import java.io.IOException;
import java.util.Vector;
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
/**
* Servlet implementation class a1servlet
*/
public class a1servlet extends HttpServlet {
private static final long serialVersionUID = 1L;
/**
* @see HttpServlet#HttpServlet()
*/
public a1servlet() {
super();
// TODO Auto-generated constructor stub
}
/**
* @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
*/
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
response.setCharacterEncoding("GBK");
//response.setContentType("GBK");
ServletContext hab = this.getServletContext();
String first=request.getParameter("first");
Vector go = (Vector)hab.getAttribute("body");
go.add(first);
//request.getRequestDispatcher("NewFile1.jsp").forward(request, response);
response.sendRedirect("NewFile1.jsp");
}
/**
* @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
*/
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
doGet(request, response);
}
@Override
public void destroy() {
// TODO Auto-generated method stub
//super.destroy();
}
@Override
public void init() throws ServletException {
// TODO Auto-generated method stub
ServletContext context=this.getServletContext();
//判斷資訊列表存在
if(context.getAttribute("body")==null){
Vector message=new Vector();
context.setAttribute("body", message);
}
}
}