Advance Servlet Understanding Set 1

How can we get context init parameter and run some code before rest of the application can service a client?

 

If you want to track active session or how many users are there? So which listener you should use.

Suppose you want to know each time request comes in, so that you can log it. Which listener is appropriate for that?

If you want to know when a request attribute has removed,added or replace, then which listener is the appropriate one?

Which listener should use to find context has been created or destroyed?

Which Listener you should use , when you want to know session attribute has added,removed or repalced?

You have an attribute class, and you want object of this type should be notified when they are bound to or removed from a session. So which listener is appropriate one?

In which of these getAttibute()  and setAttribute() method has defined?

Which one is required as a sub-element of tag  in DD?

By which tag you can pre-initialise a servlet?