The State of Java in 2019
Last updated: October 13, 2019
Mocking is an essential part of unit testing, and the Mockito library makes it easy to write clean and intuitive unit tests for your Java code.
Get started with mocking and improve your application tests using our Mockito guide:
Handling concurrency in an application can be a tricky process with many potential pitfalls. A solid grasp of the fundamentals will go a long way to help minimize these issues.
Get started with understanding multi-threaded applications with our Java Concurrency guide:
Spring 5 added support for reactive programming with the Spring WebFlux module, which has been improved upon ever since. Get started with the Reactor project basics and reactive programming in Spring Boot:
Since its introduction in Java 8, the Stream API has become a staple of Java development. The basic operations like iterating, filtering, mapping sequences of elements are deceptively simple to use.
But these can also be overused and fall into some common pitfalls.
To get a better understanding on how Streams work and how to combine them with other language features, check out our guide to Java Streams:
Explore Spring Boot 3 and Spring 6 in-depth through building a full REST API with the framework:
Yes, Spring Security can be complex, from the more advanced functionality within the Core to the deep OAuth support in the framework.
I built the security material as two full courses - Core and OAuth, to get practical with these more complex scenarios. We explore when and how to use each feature and code through it on the backing project.
You can explore the course here:
Spring Data JPA is a great way to handle the complexity of JPA with the powerful simplicity of Spring Boot.
Get started with Spring Data JPA through the guided reference course:
Refactor Java code safely — and automatically — with OpenRewrite.
Refactoring big codebases by hand is slow, risky, and easy to put off. That’s where OpenRewrite comes in. The open-source framework for large-scale, automated code transformations helps teams modernize safely and consistently.
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Join the next session, bring your questions, and learn how to automate the kind of work that usually eats your sprint time.
Regression testing is an important step in the release process, to ensure that new code doesn't break the existing functionality. As the codebase evolves, we want to run these tests frequently to help catch any issues early on.
The best way to ensure these tests run frequently on an automated basis is, of course, to include them in the CI/CD pipeline. This way, the regression tests will execute automatically whenever we commit code to the repository.
In this tutorial, we'll see how to create regression tests using Selenium, and then include them in our pipeline using GitHub Actions:, to be run on the LambdaTest cloud grid:
I’ve been running the yearly 2019 “State of Java” survey for the last couple of weeks.
In its 6th year, we had 6707 developers taking the time to go through and answer; if that was you – thank you!
Time for the results 🙂
1. Java Adoption
Even today, Java 8 is still
Not surprisingly, Java 8 is still predominantly used in production:
Clearly, Java 8 is here to stay – with a drop from last year at 84.7% to this year at 79.8%.
2. Framework Adoption
Next, let’s see what the framework story looks this year:
As opposed to Java, this is an entirely different story. Spring 4 was over 50% last year and it’s now hitting 30%, and Spring 5 went up from 24% to 58.4% today.
The Java EE / Jakarta EE numbers are also interesting – going from 9.5% last year to now 14%. The current more stable and well-understood path is clearly helping.
3. Spring Boot Adoption
On to Spring Boot – again, the adoption and the speed with which the community is moving to the latest version is impressive and speaks volumes about the maturity of the ecosystem.
Boot 2 went up from around the 30% mark last year all the way to 60.5% now:
And, the 1.4 or older is starting to drop off the chart here, which is also cool.
4. Build Tools Adoption
The build tools story is probably the most stable of all of the data here. Maven is exactly where it was last year – dominating the landscape:
5. IDE Adoption
IDEs, on the other hand, are a different story. IntelliJ is clearly winning the race here, with 61.3% (up from 55.4% last year):
Eclipse is about half of that – with 32.8% this year, down from 38% last year. Not a surprising pattern here.
6. Web/Application Server Adoption
This is the second year where I decided to ask this question – so it’s great to finally have these numbers but also the data from last year to compare to.
Tomcat is clearly still the winner here, with a cool 73% of the market (up from 62.5% – which is crazy growth).
7. Other JVM Languages
On to other languages on the JVM.
First, what’s somewhat surprising and interesting here is that 62.6% of developers are only using Java, exactly like last year (62.8%). I was definitely expecting this number to go down, given the strong adoption of Kotlin, but it looks like it hasn’t, yet:
That being said, Kotlin did still grow from 13% last year to 16.5% today.
Groovy fell from 19.3% to 17.4% today, most of that attention likely now going to Kotlin.
Scala also fell about 1.1%, now to 8.6%.
So, the trend is clear – Kotlin is chipping away at the other JVM languages, and quite successfully.
8. DBs
And, finally – DBs – with MySQL stable and PostgreSQL growing a full 5% since last year:
9. Conclusion
There we have it – a very interesting look at the Java ecosystem now, in 2019.
Some really unexpected bits of data, and definitely some not-so-unexpected ones.
All in all, a very cool look at the Java community, and again – big thanks to everyone who voted.
