I plan to do this exam by the beginning of next year, and am a bit clueless of how to prepare. There is no mock exam available as I can see, neither on enthuware, epractizelabs nor mindhub.com. See also the thread on enthuware about 1z0-900.
There is an official tutorial on java ee 7 that was recommended in a question on stackoverflow. This tutorial can be downloaded as PDF (980 pages!) and seems quite elaborated. I'm not sure if the book
(together with volume 2) is the printed version, however I will print it myself.
I ordered the book
which seems to cover most of the topics in the exam description (except maybe security), and also had a look at
, which is bigger, but seems to cover less topics.
If you haven't done any previous JEE exam it will be an enormous task. You will have to go through a number of books (or relevant specs). You might even start with preparing one of the previous EE exams and see how much work it is.
Have you read this thread? Note that Mikalai Zaikin had almost all previous EE-certifications and found this one very difficult....