In 2021 Java celebrates its 25th anniversary. As part of this anniversary Oracle offered to register for the Java SE 11 Developer exam for only 25 dollars (22 euros). This is an interesting offer, because normally this will set you back ten times as much. So I decided to go for it and to give it a shot. This offer was valid for two months, so there was a deadline to keep me focussed on my goal. In this blog I will give you some tips to pass this exam.
Before I get to this a little bit more background on myself. I did the Java 8 OCA exam in 2017 (so four years ago). Please note that this was the OCA version. The OCA version is a lot simpler than the OCP version. It will test you on far less topics. The Java SE 11 Developer is comparable to the former OCP versions.
Because of my previous experience I already knew about the kind of questions you can expect. The questions are, to put it mildly, misleading. The exam tries to trip you up with really obscure notations and almost correct options. To give an example, does the following line compile?
public static void main (String []args) {}All Java developers recognise this as the main entrypoint of a Java program. Most developers will frown their brows on the part between the parentheses. Normally we see one of the following:
I had never seen String []args before, but apparently it is allowed, so it does compile. Most questions contain several of these “interesting” cases.
So to pass this (or any other Java exams) you have to become a human compiler. You need to know if code will compile or not. Half of the questions have an option that says the code will not compile.
The first question is: Where should I start?
I used and recommend the Oracle Certified Professional Java SE 11 Developer Complete Study Guide from Jeanne Boyarsky and Scott Selikoff. This book has around 1300 (!) pages, but it has all the information that you need. It has the depth that you need to become the aforementioned human compiler. Furthermore it is also brimming with questions to test your knowledge and sharpen your skills.
This book also comes with an online test environment in which you can customize the kind of exam you like to do. For instance you can specify that you only want questions about exceptions or security. You can also create an exam with only x questions or one that only contains questions that you incorrectly answered in the past. A great tool to prepare effectively.
The exam was much more difficult than I expected when I started this adventure. It took far more time and effort than I had planned to commit to this. In the intro of this blog I mentioned passing for the OCA 8 exam. I had to study quite a lot for this exam, but leading up to the exam I was pretty confident that I would pass. For this exam I studied thrice as hard and I could not predict the outcome. So in the end I put in about 120 hours to fail at my first attempt. 😞
After spending sixty hours on studying I took my first mock exam and I failed gloriously. I only answered 40 percent of the questions correctly. The exam asks really in depth stuff, so for me just studying was not enough. I had to practice and practice to familiarize myself with all the nooks and crannies of the Java language. So I spend another sixty hours doing as many practice questions and mock exams as humanly possible. I had to do the exam twice and I barely passed it the second time.
All previous tips are about preparing for the exam. The last tip will be about the exam itself. It consists of 50 questions and you have to answer them in 90 minutes. That is 108 seconds per question. That is a scary little amount of time when you have to parse 15 lines of code. Normally you start with checking if the code compiles. So you start looking for compile errors. Once you have done that you try to understand what the code does. The code will not be straight forward. There will be strange constructs in there. There will be things that do not make sense in the real world. Finally you have to find the correct answer. This is a pretty tall order to complete in 108 seconds. Actually I was not able to do it consistently. So I had to change my approach.
I started looking at the answers before I read the question and this really sped me up. Maybe there is no answer option that says that it does not compile. So you do not have to check for compile errors. Maybe there is an answer option that says it will give a compile error at a given line. Now you can check this line for obvious errors. These are only two examples, but you can get a lot of information from the possible answers. So use this information to your advantage to get the correct answer faster.
Thank you for reading this blog and good luck passing the exam!
Update February 2022: Check out Ian van Nieuwkoop's new blog with Four more tips to pass the Java SE 11 Developer exam.