Java is still voted the third most popular programming language in the world for software solutions and there are a number of factors that make Java so popular (source: Stackify):
Portability – Thanks to the platform-agnostic Java Virtual Machine (JVM), Java can run on nearly every system. Java is also the most popular Android language, so the vast majority of Android apps are built in Java.
Scalability – James Governor has a saying: “When web companies grow up, they become Java shops”.Java is built for scalability in mind, which is why it is so popular among enterprises and scaling startups (Twitter moved from Ruby to Java for scaling purposes). Since Java is a statically-typed language, it is faster and easier to maintain with less bugs.It is also backwards compatible, which means old versions of the language will still run perfectly even after new versions are released. This is a big relief for businesses who would otherwise worry about rewriting their code every time a new version comes out.
Large community – The popularity of Java helps to ensure its future popularity, thanks to a huge community of users. With massive Stack Overflow and GitHub communities, developers can find help on virtually any problem they might encounter. Coupled with its portability, developers know that investing in Java will pay dividends for a long, long time.
We find it most popular for building back-end web applications for the core technology stack since the speed and performance is great