Learning Kotlin and Java


I’m learning Kotlin with the objective of developing Android apps.

I have extensive experience in C++ and other languages, but not Java.

I was attempting to learn Kotlin by reading the tutorials on this site, but ran into problems because they seem to assume knowledge of Java.

So I temporarily deferred my Kotlin-learning, and am working my way through the Java docs at oracle.com. Java seems very similar to C++, so it’s going pretty quickly.

Is it ok to ask Java questions here, or should I look for a Java-specific discussion forum? If the latter, can you recommend one?

I don’t think you have to learn java first just to learn kotlin. If you have extensive experience in C++ all you need to do to get started should be going through the kotlin reference page(maybe skip the interop and native and multiplatform stuff as well as possibly coroutines, although you should look into those at some point) and maybe working through koans.
That said you still should at least familiarize yourself with the java standard library as kotlin depends on it heavily (at least if you target the JVM which you do when developing for android). You can do that using kotlin or java. Although if you are at a point where you look at the java docs you should at least read the basics of the kotlin java interop, the part about getters/setters, null-safety and generics is somewhat important).
Also if you can point out where those tutorials require java knowledge this would be helpful to improve those.

The Kotlin docs seem “bare bones”, and lack an explanation of the rationale and motivation for some features and tips on when to use feature X vs. feature Y.

Maybe the problem is that it’s been a number of years since I used C++, and I need the review that the Java docs provide.

Thanks for your reply.