Difference between Filter and Listener in Servlet (Java EE)

Question

There are Filters and Listeners functionality in Servlet. I want to know exact difference between Filter and Listener.

Answer 1

Text from Java EE 6

Filter

Filter is an object which transform the request and response (header as well as content).

Listeners

You can monitor and react to events in a servlet's life cycle by defining listener objects whose methods get invoked when life cycle events occur.