Passing the 1Z0-819 Oracle Certified Professional Java SE 11: preparation and exam experience

As I found pretty few feedbacks on taking the 1Z0-819 certification (which is understandable as the certification is quite recent), I decided to share mine regarding the preparation I took for the exam as well as the exam itself.

For further preparation, you can check my OCA and OCP topics related articles in which I’ve covered most of the topics needed for the certification exam with some advice and gotchas highlights. I would advise you to cross sources and always learn from various people and courses to get the most complete and accurate information.

Where I was and why I took the OCP certification as a junior developer

First I’d like to present my situation when I took the OCP certification:

• had done the OCA Java 8 certification a year earlier: the new OCP certification now covers level I (ex-OCA) and level II knowledge, so let’s say I had already had a good training on “half” (a bit less because level II topics are bigger stronger harder) the exam topics;
• had been working in IT as a full-stack developer, mainly on Java, for a bit more than a year, but as a junior (clearly said: been manipulating Java but not intensively and not always on interesting or complicated points), however I think this helped and I would not advise someone with zero Java professional experience to take the OCP exam;
• had taken advantage of the 6 months of free access on the beta-version of the JetBrains Academy / HyperSkill platform and had done most of the Java topics, including advanced (level II) ones like multithreading, Collections framework (not only List), advanced Date/Time, Nested classes… My free access had terminated three months earlier;
• am a nerd… Every time I take a course or I do a training, I take notes and compile information in my holy notebook (or I write articles on this blog about it!), that really helps consolidating the information in my head and make sure I understand it.

I took the OCP certification thanks to the Oracle 25-years offer, which consisted of 2 months free access to the Java SE 11 path on the Oracle University website and the certification costing $25 instead of $250. I just thought “Ok, let’s give it a try, at worst I would loose 25 bucks, at best I get certified for a great price!“. They announced this on 25th of February (and didn’t make much noise about it for some reason, I’m glad I’m sniping news about my fav tech topics regularly and I saw it immediately!) and the counterpart was that the certification was to be done on 25th of April the latest (so exactly 2 months to prepare, which is great if you are full time available, and short if you’re working full time, and really short if you’re working full time and attending evening classes…). So I bought my voucher and made my appointment for the 25th of April directly.

It was a goal for me to pass that certification, although I would probably have given it a few more months, but a little challenge and anxiety rush is sometimes ok…

How I prepared for OCP certification exam

Oracle University

Because the Oracle University course was available for free for 2 months, I started with it. There was a 30 hours course on Java 11, which (I realized later) was not especially meant for certification takers and would cover topics not needed. The course was all video, while I’m more of a reader (hence, my appreciation for the JetBrains Academy course!), and the slides were covered with loads of text, which made it difficult to grab all information. Plus the speaker would go really fast on important topics.

From the 30 hours, I watched about 61%: I skipped almost all the guided practice videos, I skipped what I noticed wasn’t exam topics (like OCI related lessons), but I also often paused to read the slides before listening to the speaker.

There was a second 3 hours course dedicated to OCP certification, only covering some special topics, which was a bit more relevant but not at all complete.

Enthuware mock exams

From there, I started the mock exams with Enthuware (which I used for OCA and helped a lot). This is about 10 bucks and totally worth the spending. They are timed exams with corrections, tips… That made me really depressed because I scored poorly at almost all attempts. On the related forum (CodeRanch), the few people who gave feedback about the exam said that the level of the certification exam was really similar to the mocks of Enthuware. At that stage, there were a few days left before the certification and I was really stressed (although I shouldn’t have been because, at worst I was just loosing 35 bucks, I didn’t have any pressure but from me to pass the exam, and I had learned a lot anyway).

JetBrains Academy

I chose not to spend too much time on the mock exams and find other sources to learn and understand the topics, and complete my knowledge because everything was not mentioned in the Oracle courses.

I luckily had a new trial period on JetBrains Academy thanks to the renewal of my student license for IntelliJ, so I retook some courses (multithreading and nested classes eg).

I also did some research on the Internet for articles and Stack Overflow posts (you know, when someone asks a question about something they don’t understand on SO, there’s also that smart-ass who answers the question by explaining the topic… we love that smart-ass).

Pluralsight 1Z0-819 series

Then, like four days before the certification, I realized that Pluralsight had released a series of courses dedicated to 1Z0-819! I guess they were really fresh (I had checked a bit more than a month before and they weren’t there) and they were a reaction to the 25-years anniversary event…

Although I found them pretty late, they helped a lot! If you’re reading this: start with them, watch them all, take notes, then test your knowledge with Enthuware, and search for additional articles or videos on weak points!

I binge watched (because I was in a hurry ppl) the most relevant, useful lessons regarding my problematic topics. Most of them were great, with summaries on important points, tips and tricks, and so on.

Back to being depressed with Enthuware mocks

Still, I retook a few mock exams and failed hard. Just like the more I knew and understood, the worst I was performing. Whaaaat. I was sure I was gonna fail the certification. So I decided to make a session of meditation and accept what was: I was gonna fail but it didn’t matter, this would be for a later time, I just wasn’t ready yet. And I spent the morning of the certification cleaning my house to relax (totally irrelevant information).

(For information regarding Ethuware mocks, I’d done the 3 start exams with very few preparation, from which I passed two, then I took 5 or 6 mid-exams which I failed around a consistent 58%, then I took one final exam after Pluralsight binge-watching which I failed with 52%, and the last exams I took were the “most-missed questions” were I passed several times with 70 to 80%… No clear pattern here, idk. For OCA I had done all exams and could see a progression, for OCP it was just a mess. Stress maybe?)

How did the OCP certification exam go

I had to do the exam at home because of the Covid situation and the limit date (my local center was fully booked).

I had taken the OCA certification at my local center, then passed two Cloud related certifications at home (for Covid reason). The Cloud certifications were more theoretical but a programming certification is more practical, which can be tricky at home because you cannot have paper, you have nothing to write! Iterating over N-dimensions arrays in your head is though for example… There is a virtual whiteboard during the exam which is a pain to use so you end up doing it all mentally.

Knowing that constraint, I had done all the mocks without paper, to be prepared. I would really advise to do it in a local center when possible because knowing that someone is watching you, not being allowed to mumble, look away from the screen, write… can add to the stress. Plus you must have a place that closes entirely.

Regarding the constraints of the 1Z0-819 exam, passing grade is 68%, time allowed is 90 minutes and number of questions is 50. To compare, OCA was a pass at 65%, it had 70 questions and time allowance of 150 minutes. I had read a lot of complaints that the time was too short for the OCP. When I’m doing mocks at home I’m always pretty fast, but I remember that for OCA I finished the exam 10 to 15 minutes before the end. You get to read the questions more carefully on the D-day I guess.

So exam started, and in the beginning it felt really easy, a lot of level I questions. I got a feeling that difficulty level was raising with the questions, but that might just be a result of exhaustion because questions are supposed to be totally random.

On the whole, I didn’t find many questions to be tricky, like trying to make you fail. I only noticed one really b*tchy question* (but it’s really likely that I didn’t notice some and fell into the tricks). The exam covers topics really widely and level I questions are well present, while the mocks of Enthuware concentrate a lot on the level II topics and are really tricky. I guess the motivation of the mocks is to get you prepared to the highest difficulty so real exam goes smoothly. Thus I don’t agree with those who said that difficulty level is equivalent.

I finished the exam a little 15 minutes in advance (so again, don’t agree with the fast that timing is too tight). I re-read the first question, noticed I had fallen into a dumb trick, corrected my answer, then I was too exhausted to review the rest of it and I quit. Funny enough, the exact same thing happened when I passed OCA. So always review at least your first answer!

TOPICS

I got some questions on modules, security and nested classes, which are to my opinion important topics to focus on, plus the advanced Date/Time and Localization APIs. OOP concepts are really important too (inheritance, polymorphism, encapsulation). A few basic questions on loops, statements, conditions. I got an advanced question on Enums (can’t remember it but it made me sweat). Quite a lot of questions on lambdas and functional interfaces. Of course all other topics of the OCP were covered and the number of questions per topic is totally random so you have to be equally prepared to answer questions on all of them.

So guess what, I made it! I scored lower than OCA, with 74% vs 83%, but that really seems logical to me as the OCP is rather high-level and might be more dedicated to medior or senior developers (Oracle’s guidelines recommend at least 1.5 years experience in developing with Java, but as mentioned before a year of experience can be full of practice and learning or slow-paced and stationary…).

Also worth mentioning that any additional knowledge of general computer science topics like Operating Systems, File Systems, Design Patterns, tech vocabulary… is really a plus, and necessary to completely understand it all.

I hope I gave you some useful information on passing the OCP certification, and for topics revision have a look at the dedicated articles.

(*) The tricky question was about Resource Bundle, the trick was a typo (file name without final -s, string parameter with final -s) in the resource bundle file name when creating the Resource Bundle object.