I've just passed the 1Z0-813 (upgrade from Java 6 cert which I passed in 2009) exam today with the score of 88%
My impressions and recommendations:
- my preparation included the Scott's and Jeannie's book, as well as Enthuware mocks, sometimes I checked up the official language spec or just studied the sources directly in IDE while practicing
- I was preparing very long, but it was my fault - I started in April, only to interrupt in June because I preferred to spent my evenings on my road bike instead of learning, and then i began learning again only in October - so I had to refresh my already obtained knowledge at first
- the exam is much easier than the practice tests in the Scott's and Jeannie's book - however, I found that the Enthuware mocks are quite a bit different focused, than the exam itself was. Still it was a very good preparation method.
- in the "Last Day Test" of Enthuware I scored with 76% - this was at the beginnig of November, but I was still unsure and waited until the mid of December to make an appointment for the exam; this was a mistake - i should have gone to the exam already in November
- I wanted to make an appointment for the exam only when I'm sure I'm prepared well and I wanted to do it before the end of the year - it was a risky decision, because I hardly managed to find a free exam slot in one of the exam centres in the city where I live - at first I thought I would have to go to another city (approximately 100 km) for the exam, but then,
luckily, a new free slot appeared in my city's exam centre -> so the recommendation is not to wait till the last moment with scheduling of the exam
- there are a couple of tricky questions, for me the "non-compiler" questions were sometimes a trouble
- on my score report I had objectives of questions, which I answered incorrectly - I am wondering because some of them, I was for example 100% sure that I marked "localization" questions correctly well, apparently not
- the most important part are lambdas and streams - probably the 2/3 or 3/4 of an successful exam is to be comfortable with this topics
Yesterday I took the 1Z0-809 OCP Java 8 SE and I really profited from your post! I didn't know about enthouware's tests and I "enjoyed" them very much. They are way cheaper than the kaplan tests and most of all they work offline.
I agree that the mock exams are more difficult than the exam itself.
I must say that the exam contained a few questions with Enumeration-s and java.util.Properties, which I did not find in the OCP book of Jeanne and Scott (and that I did not know!).
I scored 75% in the last mock exam I did, and I scored 82% at the exam. I believe that the exam is slightly easier than both OCP book and enthouware exams, and it has lots of questions about the stream API and lambdas.