SessionListener

import javax.servlet.http.HttpSessionAttributeListener;
import javax.servlet.http.HttpSessionBindingEvent;
import javax.servlet.http.HttpSessionEvent;
import javax.servlet.http.HttpSessionListener;

import com.travelsky.tibetair.service.vo.UserVo;

/**
 * 测试耍的。哈哈哈，监控session的变化
 * @author hjc
 * @version 2011-4-8
 */
public class SessionListener implements HttpSessionListener,
		HttpSessionAttributeListener {

	public void attributeAdded(HttpSessionBindingEvent arg0) {
		 System.out.println("【监听到】HttpSession对象中新增一名为" + arg0.getName()
	                + "的属性,其属性值为" + arg0.getValue());
		if (arg0.getValue() instanceof UserVo) {
			UserVo new_name = (UserVo) arg0.getValue();
			System.err.println("现在的用户是："+new_name.getUser().getUserName());
		}

	}

	public void attributeRemoved(HttpSessionBindingEvent arg0) {
		 System.out.println("【监听到】HttpSession对象中一名为" + arg0.getName()
	                + "的属性被删除!");
		 if (arg0.getValue() instanceof UserVo) {
				UserVo new_name = (UserVo) arg0.getValue();
				System.err.println("现在的用户是："+new_name.getUser().getUserName());
		}
	}

	public void attributeReplaced(HttpSessionBindingEvent arg0) {
		 System.out.println("【监听到】HttpSession对象中一名为" + arg0.getName()
	                + "的属性被修改！新的 值是"+arg0.getValue());
		 if (arg0.getValue() instanceof UserVo) {
				UserVo new_name = (UserVo) arg0.getValue();
				System.err.println("现在的用户是："+new_name.getUser().getUserName());
		}
	}

	public void sessionCreated(HttpSessionEvent arg0) {
		 System.out.println("【监听到】新用户" + arg0.getSession().getId() + "上线！");

	}

	public void sessionDestroyed(HttpSessionEvent arg0) {
		 System.out.println("【监听到】新用户" + arg0.getSession().getId() + "下线！");

	}

}