9 Things Java Programmers Should Learn in 2019

May 31, 2018 · 8 min read
“Coffee in a cup with latte art in the milk in Lancaster” by on

Being a Java developer and the author of a , I frequently receive requests from Java programmers from all over the world asking how they can improve themselves.

In the past, I have shared my , and every tip in that article still holds true, but given that it’s a new year, I have decided to jot down new tips for Java programmers to improve themselves, enhance their knowledge of Java programming, and increase their value for future career growth.

So without wasting any more time, let’s see my nine ideas for Java programmers in 2019. You can take inspiration from these ideas to create your own goals.

By the way, folks, In this post, you will not only find what to learn but also where to learn as many of my readers often comes back to me that how they can improve certain skills, where to start, etc.

1. Learn Java Performance Tuning

In the last a couple of years, I have taken more than , and one skill that I clearly see lacking is knowledge and understanding about JVM internals, GC behavior, and Java performance tuning.

Learn JVM Internals

As your Java experience grows and you become a senior Java developer with more than 5–6 years of experience, it’s expected from you to know both the big picture and the small details about Java’s fundamentals.

If you can’t profile an application or cannot figure out why it’s slow or how to make it fast, then you should read a good book on JVM internals and performance tuning, e.g Scott Oaks’ best seller

I have been reading it for years and still refer to it whenever I get time. My goal is to read it again this year.

If you prefer online courses over books, then I suggest you take a look at series of courses on Pluarlsight, which explains memory management, class loading, Security, and Reflection.

2. Code Everyday for 2 hours

Another thing I noticed last year is that as your experience grows, you spend your time on coordination, replying to emails, being a catalyst, troubleshooting, mentoring, and generally being a project manager kind of person.

Code, Code, and Code

What you left behind is , which is the single most important skill for a programmer.

If you feel that you are not doing enough coding, then make a resolution to code every day. At least, write something, be it on your project, an open source framework, a library, or a utility.

Since starting is the most difficult thing, I suggest that any time you feel resistance, start reading and refactoring code for fun. You will enjoy that and, in the process, you will also write code.

You can also solve problems given in . This will not only make sure you’re ready for an interview, but also improve your knowledge of data structures, algorithms, and programming logic.

3. Profile Your Java application Once a Month

This tip is attached with the first tip about reading a and or . Btw, Just reading the book or joining a course will not be enough. You have to apply that knowledge in your live project.

I suggest you , at least once a month and spend a good amount of time understanding and analyzing the results.

You can also take a heap dump of your Java process, or, if you had a recent crash, then take that heap dump and find out which object is taking most of your memory. Is there a in your Java application?

What is the cause? What will happen if other 100K new clients access your application? If you can answer all these questions comfortably, then you are in good shape. If you need some guidance on solving memory and CPU issues, I suggest you take a look at by Richard Warburton.

4. Participate in Coding Challenges

This goal is, again, somewhat related to our second resolution — write code every day for 2 hours. Let’s face it, sometimes, you don’t have enough chances in your live project to .

If you are starving for challenging code, then there is nothing better than participating in programming and coding challenge.

There are many websites on the internet that host programming challenges and give you the opportunity to test your skills, but is simply the best.

If you are looking for some tough programming challenges, then you can also check out my .

5. Learn Network Programming in Java

One more thing I have learned from is that Java developers need to improve their socket programming and networking fundamentals.

I have asked many questions from my list of Java networking programming questions, but most developers fail to answer most of them.

Some of them even struggle to outline the key , which I thought was too basic to ask any Java developer of 2–5 years of experience.

If you feel that you have not gotten enough opportunity to learn socket programming in Java or that you don’t need to because you are Java web developer working with , Servlet, and JSF, then I suggest you read at least one good book on Java networking, NIO, and socket programming.

One book I highly recommend is . It’s easy to read, interesting, and a good way to learn the fundamentals of socket programming.

6. Java 12

Last a few years have seen a couple of big releases, and one of them was JDK 12. I have yet to start with JDK 11, forget about 12, but this is the first thing I am going to look into in 2019.

If you want to learn new features of Java 9 like Jigsaw, Reactive Streams, API enhancements, etc., then the is a good course to start with.

Similarly for like var for local variables you can check a good course on Java 10 like which is also most up-to-date and recently updated for Java 11 as well.

7. Spring 5.0

Another big release for the Java world in 2017 was Spring Framework 5.0. With lots of exciting features, e.g. reactive programming model and adoption of Java 8 and 9, Spring 5.0 adoption is going to speed up in 2019, and that’s why every Java developer should learn it. If you need some help, is a good course to start with.

8. Spring Security 5.0

Another interesting release of 2017, which I am going to learn in 2019, is Spring Security 5.0. Spring Security 5.0 was a major release, and they rewrote a couple of modules and fixed several hundred bugs.

The most interesting part is the OAuth 2.0 module. Unfortunately, there are not many resources to learn Spring Security 5.0 at the moment, but thankfully, Eugen has updated his to cover version 5.0 and also added a new module on OAuth 2.0.

9. Unit Testing

If you want to become a better developer in 2019, then you should work on your unit testing skills. And not just unit testing, but automated testing in general. This also includes integration testing.

You can learn and other advance like Mockito, PowerMock, Cucumber, and Robot Framework to take your unit testing skill to the next level.

Mockito is really powerful and allows you to write a unit test for complex classes by mocking dependencies and just focusing on the objects under test.

If you are a beginner in unit testing and want to learn it in 2019, then the from Udemy is a good starting point.


That’s my advice! If you are a Java programmer with a couple of years of experience, you can also take inspiration from this list to set your goal. Some other things you can add to this list are learning , , and , as those are essential for any Java programmers.

I have purposefully kept this simple and achievable because I personally believe that small successes lead to big successes.

Setting small goals and achieving them is better than setting big, impractical goals and failing before kick-off.

So what are you waiting for? Write down your goals for this year and share them with us. At the end of the year, you can come back here and tell us about how much you achieved.

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Closing Notes

Thanks for reading this article so far. You might be thinking that there is so many stuff to learn, so many courses to join, but you don’t need to worry.

There is a good chance that you may already know most of the stuff, and there are also a lot of useful which you can use, I have also linked them here and there along with best resources, which are certainly not free, but worth of money.

At the end of the day, you should have enough knowledge and experience about the things mentioned here.

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Written by


I am Java programmer, blogger, working on Java, J2EE, UNIX, FIX Protocol. I share Java tips on http://javarevisited.blogspot.com and http://java67.com


An humble place to learn Java and Programming better.