This week's book giveaway is in the OCPJP forum. We're giving away four copies of OCA/OCP Java SE 7 Programmer I & II Study Guide and have Kathy Sierra & Bert Bates on-line! See this thread for details.
This topic has been discussed before but I could not find the messages. I have a data class that has to implement an interface DB. Can I create another interface that extends DB and have my data class implement the new interface instead of DB. Will this break the requirement that data has to implement DB. Because after all it is implementing DB just not directly.