IntelliJ IDEA’s Java and Kotlin for Cursor and VS Code Hits 1.0

Ten weeks ago, we opened up a preview of an LSP-powered extension that brings IntelliJ IDEA’s smartness for Java and Kotlin into VS Code and Cursor. As mentioned in that blog post, this is part of a bigger initiative: moving our JVM intelligence to wherever our users are, no matter what editor or agent they are using.

Today, we’re proud to announce 1.0, the first stable release of Java and Kotlin by IntelliJ IDEA.

And we’re not shipping it alone. This release is also the result of a close collaboration with the team at Cursor, who have worked alongside us to make Java and Kotlin a first-class experience in their development environment.

Get Java and Kotlin by IntelliJ IDEA from Visual Studio Marketplace

Get Java and Kotlin by IntelliJ IDEA from Open VSX Registry

Why this matters

Agentic development is changing how software gets built. As agents take on more implementation work, developers spend less time manually editing code – and when they do edit, they often need only a focused set of features: navigating to declarations, finding references, code completion, and renames.

These capabilities are exactly what the Language Server Protocol was built for: implementing language support once, and reusing it in any LSP-capable editor. And it’s not only humans who benefit. Agents can call into an LSP directly, producing faster, more deterministic results – and, importantly, consuming fewer tokens.

These are the workflows we want to accommodate with our extension and the underlying IntelliJ IDEA’s Language Server and Debug Adapter.

Cursor collaboration

When we set out to bring IntelliJ IDEA’s language intelligence beyond our own IDE, Cursor was a natural first partner.

Their team collaborated closely with us throughout the development of the extension, battle-testing it and making sure Java and Kotlin developers get a seamless experience inside Cursor from the moment they open a project.

We’re glad to work with JetBrains to bring Java and Kotlin language intelligence to Cursor. With Java and Kotlin by IntelliJ IDEA, developers get IntelliJ IDEA’s code analysis, navigation, and refactoring while they work with Cursor’s agents. — Rohan Shah, Product, SpaceX AI

What’s in 1.0

Java and Kotlin by IntelliJ IDEA is powered by the same Java and Kotlin language technology as the IntelliJ IDEA desktop IDE. 1.0 brings a focused set of capabilities to VS Code and Cursor, including:

• Java, Kotlin, and mixed-language project support
• Smart code completion, navigation, and code analysis
• Refactorings and editor assistance
• Maven, Gradle, and Bazel build tool support
• Fast, reliable performance even on large projects and monorepos
• Support for test runners right now for JUnit
• Powerful debugging capabilities, including emulated breakpoints and async stack traces

The full feature list is in our documentation.

For Cursor, there is dedicated support for the Agents Window. It may use its own instance of the Language Server to provide analysis capabilities based on IntelliJ IDEA’s inspections. This includes nullability support with JSpecify and for Spring Framework’s specifics.

Getting started

Install Java and Kotlin by IntelliJ IDEA from the Visual Studio Marketplace or the Open VSX registry.

Install from Visual Studio Marketplace

Install from Open VSX Registry

Once installed, open your Java or Kotlin project in VS Code or Cursor. The extension analyzes your project, imports it based on any Maven, Gradle, or Bazel build files it finds, and enables Java and Kotlin language features in the editor.

Compatibility notice

Java and Kotlin by IntelliJ IDEA includes code analysis and quick-fixes that overlap with Red Hat’s and Oracle’s Java extensions. To avoid duplicated or conflicting behavior, we recommend disabling those extensions while using ours.

We have, however, made sure that our extension works well with others, like Spring Tools from the Spring Team.

Licensing

With version 1.0, the extension moves out of its free preview phase. Using it now requires an IntelliJ IDEA Ultimate subscription after a 30-day trial period during which you can try out its full feature set for free.

The same license covers IntelliJ IDEA’s Java and Kotlin capabilities everywhere you work – the IntelliJ IDEA desktop IDE, VS Code-based editors like Cursor, and other supported environments. You can review pricing here.

Note: The license is explicitly designed for human use; we’ll release an update regarding licensing models for purely agentic use soon.

Coming next: Agentic and terminal-based workflows

Java and Kotlin by IntelliJ IDEA 1.0 in the editor is just one milestone.

In one of the next releases, agents that you orchestrate in the Agents view in Cursor or VS Code will also be able to call the LSP directly when writing code, leading to faster, better, or cheaper results.

In parallel, we’ve been running experiments applying the same LSP- and DAP-backed intelligence to fully agentic, terminal-based workflows – think Claude Code or Codex calling directly into IntelliJ IDEA’s Java and Kotlin understanding. News on this will also be announced soon.

Feedback and support

We’re still listening – Java and Kotlin by IntelliJ IDEA 1.0 is a milestone, not the finish line. Tell us what works, what doesn’t, and what you want next. Leave a comment here, open a ticket in our issue tracker, or submit a support request using this form.

Thank you to everyone who tested the preview, and to the Cursor team for launching this with us.