This week's book giveaway is in the OCAJP 8 forum. We're giving away four copies of OCA Java SE 8 Programmer I Study Guide and have Edward Finegan & Robert Liguori on-line! See this thread for details.
Annotations are introduced in java 1.5 and the same annotation processing technique has been implemented in servlets to support annotations for configuring and other process. This reduced the burden of configuring xml files and more. For example @WebServlet,@InitParam etc.
No pain, No gain.
OCJP 1.6, Liferay Certified Developer 6.1