Kotlin/Java

Lesson in the Kotlin Roadmap · Stage 44: Kotlin/Java

Last updated 14 September 2026

What is Kotlin/Java?

Kotlin/Java allows Kotlin code to seamlessly interact with Java code and libraries. This interoperability means you can use existing Java code in your Kotlin projects and vice versa. It leverages the Java Virtual Machine (JVM) to run both Kotlin and Java code, enabling developers to gradually migrate Java projects to Kotlin or use Kotlin for new features in existing Java applications.

Study this in the interactive course See the whole Kotlin roadmap

Free resources to learn Kotlin/Java

Official docsGet started with Kotlin/JVM
Official docsMixing Java and Kotlin in one project – tutorial
VideoKotlin For Java Developers Complete Course

Kotlin/Java: common questions

Can I learn Kotlin/Java in Hindi?

This lesson is written in English. Once you sign in, open it in the interactive course and ask the AI tutor to explain Kotlin/Java in Hindi or Hinglish. The tutor answers from this lesson’s own text, so it stays on the syllabus, and it runs on your own Google, OpenAI or Anthropic key.

Is this Kotlin/Java tutorial for beginners?

It is lesson 129 of 153 in the free Kotlin roadmap, in stage 44, Kotlin/Java. If you are new to Kotlin, start from stage 1 and come back here in order; if you already know the earlier stages, this lesson stands on its own.