Instantiating extra objects not directly visible in code.Boxing primitive types, which allocates short-lived objects.In particular, I’ll mention each time a Kotlin feature involves: You can then press the “Decompile” button in order to read the equivalent Java code. With the Kotlin plugin installed in Android Studio, select the “Show Kotlin Bytecode” action to open a panel showing the bytecode of the current class. This is the tool of choice to figure out how Kotlin code gets translated to bytecode. These articles will focus solely on the JVM/Android implementation of Kotlin 1.1, not the Javascript implementation. “With great power comes great responsibility.” Kotlin is powerful and some famous quote says: This is not a case against Kotlin: I like the language a lot and it increases productivity, but I also believe a good developer needs to know how language features work internally in order to use them more wisely. Kotlin is a modern programming language with a lot more syntactic sugar compared to Java, and as such there is equally more “black magic” going on behind the scenes, some of it having non-negligible costs, especially for Android development targeting older and lower-end devices.

Now that Kotlin is officially supported by Google in Android Studio 3, I thought it would be a good idea to write about that aspect of the language by studying the bytecode it produces. Around the same period he also started advocating the use of the Kotlin language for Android development but barely mentioned the hidden costs of that language, aside from recommending the use of inline functions. In 2016, Jake Wharton gave a series of interesting talks about Java’s hidden costs.

Kotlin internal meaning