Yes the classes are mandatory, but you do not have to take it before the exam, rather, you can take it at any stage as you progress through certification process.
As of whether to take 1Z0-864 or 1Z0-807 - everyone decides for himself, if you want less risk and more predictability, go with (older) 1Z0-864, but if you want to learn some exciting new stuff of Java EE6 and are willing to take some risk - you should try 1Z0-807.
I did it it myself, passed from 1st attemtpt, and I really enjoyed the process.
I started studying for the 1Z0-807 on January 7th.
I knew I would have to read a lot of books, and it wouldn’t be fast. I knew I would spend a few months for the preparation. So below is the list of books I’ve read for the exam.
IT Architectures and Middleware... by Britton/Bye (this book is just good overall. It lays a solid foundation for the software architecture. You may not need it for part 1, but I still recommend it)
Patterns of Enterprise Application Architecture by Martin Fowler (Actually, I read this book long ago, but used as a reference while reading other patterns books. Very good book, timeless classics)
SOA in Practice by Nicolai M. Josuttis (again, I read this book long ago. It delivers some useful concepts of SOA, like orchestration and choreography, that are in the exam and that I could not find anywhere else)
UML Distilled by Martin Fowler et al (UML is not part of 1Z0-807, so you do not need it for OCMJEA6 Part 1)
Sun Certified Enterprise Architect for Java EE Study Guide (2nd Edition) by Cade and Sheil (although it is for SCEA5, I think it is still very important book. Must read)
Design Patterns by GoF (Not all GoF patterns survived transition to 1Z0-807, so you may want to read only those patterns that are in the objectives)
Core J2EE Patterns: Best practices and Design strategies by Depak Alur et al (controversial one. Some of patters from this book became anti-patterns with Java EE6. Only read presentation layer patterns, since they are still in 1Z0-807. Do not read the rest)
Real World Java EE Patterns - Rethinking Best Practices by Adam Bien (10 out of 10. Awesome book. JEE6 in a nutshell. It also has infrastructural patterns that were introduced in 1Z0-807)
Bitter Java by Bruce A Tate (this book, and the next one, are outdated, however they describe certain so called “anti-patterns” that are included in 1Z0-807. Skim through this and next book briefly, only to grasp basic ideas about these anti-patterns. Do not spend more than 2 days on either of them)
Bitter EJB by Bruce A Tate (same as for Bitter Java. Do not spend much time on this one)
Oracle Certified Master, Java EE Enterprise Architect by Amritendu De (this is a collection of mock questions for OCMJEA5, not a tutorial of any kind. Questions from this book are somewhat oversimplified, expect that real exam will be more difficult. This book also covers part 2 and part 3)
OCM Java EE 6 Enterprise Architect Exam Guide became available on Amazon not long ago. I did not read this book so I cannot comment on it.
I did not read Head First Design Patterns, but people who I trust told me that this book is very good. Consider it as an alternative, if not primary, source of information about GoF patterns. I have read a number of other books from "Head First" series and I liked them all.
When I was studying for the exam, I was making notes using google docs. I shared some of them here at coderanch, you can find links to my notes, along with a lot of other very useful information, in SCEA online resources section.
I passed 1Z0-807 with the score 78% on June 7th, and so I spent 5 month exactly for the preparation.
This is about it, let me know if you more questions.
The information you gave about the books to prepare for the Architect exam is very useful, Thanks
I have few questions about how i should prepare for the exam.
1) SOA in Practice - how detailed i should read this book, can i just skim through the topics or need to read each and every line Same for IT Architectures and Middleware (how detailed the reading should be).
2) UML Distilled - are there any UML questions in Part 1 or is this book more useful for 2nd and 3rd parts of the exam.
There is no UML questions at all in Part 1, and you can only skim through SOA in Practice for Part 1.
You will definitely need UML, along with OOD, data modeling and possibly even domain driven design for the Part 2, so it should still be in your agenda.
And SOA in Practice is a good book, and not very long one, so you may want read it slowly at some point after taking Part 1