How Java Open-Source Projects Use IntelliJ IDEA: Real-World Examples – Part 1
At JetBrains, we build tools to help developers stay focused and productive, and we’re especially proud when those tools help power the open-source projects that developers around the world rely on every day. Shaping the direction of Java development, such projects contribute substantially to the vibrant Java ecosystem. This two-part series highlights some of the […]


At JetBrains, we build tools to help developers stay focused and productive, and we’re especially proud when those tools help power the open-source projects that developers around the world rely on every day. Shaping the direction of Java development, such projects contribute substantially to the vibrant Java ecosystem.
This two-part series highlights some of the most impressive open-source Java projects we support. From testing frameworks and HTML parsers to innovative web libraries and languages, each of these projects reflects the creativity and ingenuity of the Java community. In each case, JetBrains IDEs like IntelliJ IDEA help developers ship faster, work more confidently, and write better code.
☕ Spring Framework
The world’s most popular Java framework.
Spring needs little introduction. It’s the backbone of modern Java server-side development, with a strong focus on simplicity, productivity, and the developer experience. JetBrains shares those values, and the close collaboration between the Spring and JetBrains teams promotes synergies for server-side developers worldwide.
Feedback from the Spring team helps ensure IntelliJ IDEA offers a seamless, intuitive experience for Spring developers – even as new features are introduced. Kotlin also continues to shape Spring’s direction: null-safety support introduced in Spring Framework 5 is evolving in version 7 with JSpecify annotations, benefiting both Java and Kotlin users. — Sébastien Deleuze, Spring Framework core committer
The Spring community is now focusing on Spring AI – an application framework that brings Spring’s principles of modularity and portability to the AI domain using familiar POJO (Plain Old Java Object) patterns, with support for both Java and Kotlin. The team also continues to invest in runtime efficiency through GraalVM native image support, Project Leyden JVM optimizations, and clever defaults in Spring Boot. Mature parts of the framework are evolving too, with features like client-side API versioning on the way.