Tomcat session数量能统计吗？

Question

如题

Answer 1

个人认为可以：在application中定义一个数量，利用HttpSessionListener在session创建时＋1，session销毁时-1.

Answer 2

package web;import javax.servlet.ServletContext;
import javax.servlet.http.HttpSession;
import javax.servlet.http.HttpSessionEvent;
import javax.servlet.http.HttpSessionListener;public class CountListener implements HttpSessionListener {
 private int count=0;
public void sessionCreated(HttpSessionEvent arg0) {
System.out.println("sessionCreated");
count++;
HttpSession session=arg0.getSession();
ServletContext sctx=session.getServletContext();
sctx.setAttribute("count", count);


} public void sessionDestroyed(HttpSessionEvent arg0) {
System.out.println("sessionDestroyed");
count--;
HttpSession session=arg0.getSession();
ServletContext sctx=session.getServletContext();
sctx.setAttribute("count", count);
}}web.xml<listener>
<listener-class>web.CountListener</listener-class>
</listener>记得结贴哦

Answer 3

package com.test;import javax.servlet.http.HttpSessionEvent;
import javax.servlet.http.HttpSessionListener;
class SessionCountListener implements HttpSessionListener{
 public static long sessionCount=0;
  @Override
  public void sessionCreated(HttpSessionEvent arg0) {
    sessionCount++; 
  }  @Override
  public void sessionDestroyed(HttpSessionEvent arg0) {
    // TODO Auto-generated method stub
    
  }  
}web.xml
<listener>
    <listener-class>com.test.SessionCountListener</listener-class>
</listener>调用：SessionCountListener.sessionCount