While going through Whizlab’s questions for Collections & Generics, I found quite a few of questions with NavigableSet, NavigableMap, ConcurrentSkipList, etc.

So I decided I will learn those also for the exam. A good way to start is this link:

http://www.javabeat.net/articles/4-what-is-new-in-java-60-collections-api-1.html

You can find a very concise article about Java Generics on IBM’s website :

http://www.ibm.com/developerworks/library/j-jtp01255.html

 It explains quite nicely why Generics are the way they are. It touches type erasure, covariance, T type contructor, and others ( still reading ).