First, it looked at where most Java developers are based. According to the Developer Estimation Model by the Market Research and Analytics Team, there are about 5.2 million developers that use Java as their primary language. JetBrains estimates that this number would be closer to 6.8 million if factoring in developers who mainly use other languages, but also use Java a little bit.
The largest concentration of Java developers is in Asia, where 2.5 million developers use it as their primary language. JetBrains believes this may be due to the fact that it is common to hire offshore developers in countries like China and India to build Android apps. “We might have expected the USA to have a high percentage of Java users, but it also makes a lot of sense that they don’t. There is a big technology stack to choose from and often a lot of the tech companies are at the forefront of that stack, so it could be that developers there don’t need the power or stability of Java and are using languages that allow them to build and test quickly,” JetBrains wrote in a post.
When looking at what types of software is developed with Java, web services was the highest at 52%. Following were small apps for small tasks (36%), databases (32%), and system software (26%).
The industries where Java is most prevalent are IT services and finance. “The Finance and FinTech sector is mostly about financial exchanges, retail banking systems, creating calculating engines and developing homegrown custom tools and services to make the company competitive on the market. Finance and FinTech are pretty much established in Java so there is no surprise here. This is the same with IT Services, as many payroll systems and inventory management services for non-IT companies are built on Java,” JetBrains wrote.
The third most popular industry was mobile development, which JetBrains doesn’t find surprising given that most Android applications are written in Java.
The company also looked at tooling for Java. The most popular version of Java is Java 8, which is used by 75% of Java developers. The most popular application server is Apache Tomcat, and JBoss EAP and WildFly have both halved in use over the past three years. The most popular framework is Spring Boot, with 61% of developers using it, followed by Spring MVC at 42%. The most popular IDE is JetBrains’ IntelliJ IDEA, with 72% of users using it, followed by Eclipse at 13%.