package com.jspservletcookbook;

import javax.servlet.*;
import javax.servlet.http.*;
import java.util.Date;

public class SessionListen implements HttpSessionListener {
    
    private int sessionCount;

    public SessionListen() {
        this.sessionCount = 0;
    }
    
    public void sessionCreated(HttpSessionEvent se){
        HttpSession session = se.getSession();
        session.setMaxInactiveInterval(60);
        synchronized(this){
            sessionCount++;
        }
        String id = session.getId();
        Date now = new Date();
        String message = new StringBuffer(
          "New Session created on ").
            append(now.toString()).append("\nID: ").
              append(id).append("\n").append("There are now ").
                append(""+sessionCount).append(
                  " live sessions in the application."). toString();
        
        System.out.println(message);
     }
    
    public void sessionDestroyed(HttpSessionEvent se){
        
        HttpSession session = se.getSession();
        String id = session.getId();
        synchronized(this){
                --sessionCount;
        }
        String message = new StringBuffer("Session destroyed" + 
          "\nValue of destroyed session ID is").
              append(""+id).append("\n").append(
                "There are now ").append(""+sessionCount).append(
                  " live sessions in the application.").toString();
        System.out.println(message);
     }
}