You can see how some Kotlin Multiplatform projects are using source source sets such as “commonMain” where common code used for all platforms is kept, and then you can have additional source sets like “iosMain” for platform specific implementations. It’s being used for Kotlin Multiplatform to create code that runs on iOS, it’s used in Kotlin Native to get blazing fast, low level speed and Kotlin JS to run in your Node server or web application. Kotlin is more than just a programming language used on Android. The answers above only apply for Android only projects. OkHttp does it, but realize this is because it’s a Kotlin only project that is meant to be used on multiple platforms (including the JVM & Android).This comes with the configuration overhead of each module, but if you share Gradle config between multiple projects, you’d only have to do this once. Some projects are 100% Kotlin, so having this directory structure clearly calls this is a single to only write code in Kotlin.While this is nice idea, from a pragmatic standpoint, having all your code in a single place is the ideal for discovery and browsing in my opinion. Some projects like the clean separation of the languages into different directories.

There are no longer issues with the Kotlin Gradle Plugin which prevented you from mixing Kotlin and Java code in the same directory.Ģ1% of people say it should go in “src/main/kotlin”.This can help maintain consistency to have all your code in one location for any project that has or had Java code in the past. I personally really like it for the reason that all of your source is in a single place, making it easier to find related code in a project mixed with Java.When you create a new project Kotlin project in Android Studio, it uses “src/main/java” as the location for your Kotlin code.The official documentation Android Developer Documentation recommends it, and shows additional configuration you must add to support a “src/main/kotlin” source set.Where do you put your Kotlin code in your Android project?ħ9% of people say it should go in “src/main/java”. My answer is always it depends, but let’s see why you would use “src/main/java” the majority of the time, and why you’d want to use “src/main/kotlin” in some cases.

Based on the results of a poll of 371 Android developers, the majority of responses endorse using “src/main/java” for Kotlin code in Android only projects.

Kotlin to java android studio