我有时候会想，网页上的点击率是怎么算出来的呢？今天学到了一个方法。
用jsp内建对象application就可以做到。
思路：
先获取代表某个页面的counter_name参数的值，也就是某个页面被访问了几次，将值保存在count中，
count=Integer.parseInt( (application.getAttribute(counter_name).toString()));
再把count值加1，然后再保存到counter_name里。
application.setAttribute(counter_name,new Integer(count));
实例程序：
test_counter.jsp
<%@ page contentType="text/html; charset=gb2312" language="java"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312" />
<title>使用计数器的例子</title>
</head>
<body>
application 对象应用示例 <br>
<jsp:include page="counter.jsp">
<jsp:param name="counter_name" value="test_counter"/>
</jsp:include>
</body>
</html>
count.jsp
<%@ page contentType="text/html; charset=gb2312" language="java"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312" />
<title>无标题文档</title>
</head>
<body>
<%
int count=0;String counter_name=request.getParameter("counter_name");
try{
count=Integer.parseInt((application.getAttribute(counter_name).toString()));
}catch(Exception e){
;}
out.println("自从应用服务器启动后，此页面已经访问了"+count+"次");
count++;
application.setAttribute(counter_name,new Integer(count));
%>
</body>
</html>
