There is at least one new class covered on the Java 6 version of the exam. I cannot remember the name at this moment but it has been discussed previously in this forum. You can *probably* pass using the Java 5 material but you should definitly research the new class(es) covered.
I took the exam too. And I got only one question from java 6. The question was about the class Console. I prepared from Sierra and Bert's book and then I studied the three new classes/interfaces (Console, NavigableSet and NavigableMap) just from the java doc API. I think it should be enough. Good luck with it!!
If you already have the 1.5 book you really don't need the 1.6 book - much as I'd love for you to buy it
Seriously, as indicated correctly in this thread there is just one new class and two new interfaces in the SCJP 6 exam and those can be studied from the API docs. The Console class is pretty easy, and the Navigable collections aren't much harder. If you compare say the old TreeMap class to the new TreeMap class, you can find which methods are new and just add those new methods to your studies.
If you don't already have the new book, and you plan to buy a copy of the book, I'd recommend the new one - we fixed some errors, we wrote some new mock exam questions, we added a few small topics that should have been in there last time , and we added discussions for the SCJP 6 exam.
So, i wouldn't say that's enough to warrant replacing the old book with a new one, but if you don't have either, the new one is better
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