JBridge: Certification Question Of The Day

The Answer

The correct answer is A: a ServletContextListener detects the start and close of a web application. Strictly speaking, it detects the initialization and destruction of the ServletContext. However, there is only one ServletContext per web application, initialized just after the web application starts and destroyed just before the web application closes. I rest my case, but feel free to challenge my assertion!
Answer B is wrong: servlets themselves have built-in methods to deal with their own initialisation and destruction.
Answer C is wrong: it is the ServletContextAttributeListener which listens for the addition, removal or change of attributes to the ServletContext.
And similarly, answer D is wrong, as there is an HttpSessionListener which detects the creation and destruction of HttpSessions.