I checked in Head First Servlet Servlet and JSP. It tells
"A plain old HttpSessionAttributeListener is just a class that wants to know when any type of attribute has been added, removed or replaced in a Session. But the HttpSessionBindingListener exist so that the attribute itself can find out what when it has been added to or removed from Session."
sorry Ranchers , I cant' find the better opportunity to extend the Thread ,What do you mean by a particular Object as Servlet is a ThreadBased and for every Thread the Object will be unique so my doubt is how this is achieved.
sorry once again for not posting a new topic.
If you want something you never had do something which you had never done
RaviNada the concept is not about a particular Servlet object. It is about a particular object that is added or removed from the Session. Suppose I implement a class which implements the HttpSessionBindingListener interface. Now when I add an object of that class into a session, the valueBound method of my class will be called. Similarly when an object of my class is removed from a session, then the valueUnbound method of my class will be called...