What the 2020 JetBrains Survey Reveals About Java Developers Worldwide

Recently, the well‑known development‑tool vendor JetBrains published an interesting data analysis of the Java ecosystem on the occasion of Java’s 25th anniversary.

Full article: https://blog.jetbrains.com/idea/2020/09/a-picture-of-java-in-2020/

The analysis produced many noteworthy conclusions, which are summarized below.

How many Java developers are there?

Professional Java developers: about 5.2 million.

Including developers who mainly use other languages but also use Java: about 6.8 million.

Where are Java developers located?

Asia has the largest number, roughly 2.5 million.

China leads, followed by South Korea, accounting for 51% and 50% respectively.

Programming language usage share

According to the 2020 Developer Ecosystem Survey, more than one‑third of professional developers use Java as their primary language, making it the second most used language after JavaScript.

JavaScript and Java dominate because many Java developers also write front‑end code or quick scripts in JavaScript.

Python likely ranks third due to the rise of machine learning.

Web technologies (HTML, CSS, PHP) remain essential.

SQL persists because virtually every application needs a database.

C++ stays strong for embedded applications.

C# appears to lose ground, possibly because it overlaps with Java in functionality.

What do Java developers build?

Web services are the most popular domain, accounting for 52% of Java projects.

Java’s presence in business intelligence, data science, and machine‑learning is surprising, as these areas are often associated with Python.

Main industries using Java

IT services (42%) and finance/fintech (44%) employ the majority of Java programmers.

In finance and fintech, Java powers trading platforms, retail banking systems, computation engines, and custom tools that boost market competitiveness.

IT services rely on Java for payroll systems, inventory management, and other enterprise applications.

Mobile development benefits from Android, which is Java‑based.

Big data and analytics still see Python leading, but Java/JVM languages have backend roles.

Software development tools, such as JetBrains IDEs, are built with Java.

Java version preferences

Java 8 remains the most popular version.

Oracle’s rapid release cadence (new version every two years) means versions 9, 10, 12, 13 received only six months of support, explaining their low adoption.

Java 13’s high usage reflects its status as the newest release at the time of the survey; numbers are expected to decline.

Java 11, released in 2018, is the latest long‑term support (LTS) version. Many enterprises hesitate to upgrade due to concerns about breaking changes from Java 9, new licensing, and subscription models.

Most popular application servers

Apache Tomcat is the clear leader.

Jetty ranks second, though its usage appears lower, possibly because many developers use Spring Boot’s embedded server without noticing the underlying server.

Top five web development frameworks for Java

Spring Boot is the most popular, followed by Spring MVC.

The survey confirms Spring’s dominance in the Java web‑development space.

Top five Java development tools

IntelliJ IDEA’s market share grew from 55 % in 2018 to 72 % in 2020, while other IDEs have been gradually losing ground.