This week's book giveaway is in the OCAJP forum. We're giving away four copies of OCA Java SE 8 Programmer I Study Guide 1Z0-808 and have Jeanne Boyarsky & Scott Selikoff on-line! See this thread for details.
Abstract Classes vs. Interfaces It may also be instructive to look at real-life implementations, for example, the Java Collections Framework, which makes good use of both interfaces and abstract classes. [ September 09, 2008: Message edited by: Joe Ess ]