Kotlin

Main

• Describe nullability and null safety
• What is the difference between nested classes and inner classes?
• What scope function do you know?
• Describe visibility modifiers
• What do you know about Any, Nothing, Unit types?
• What do you know about default methods in interface?
• What is destructuring declarations?
• What is Ranges?
• What is Sequence?
• What is the difference between == and === ?
• What do you know about extensions?
• What is infix function?
• What is init block?
• What do you know about companion object?
• What do you know about delegated properties?
• What do you know about JvmOverloads annotation?
• What do you know about JvmStatic and JvmField annotations?
• What do you know about generics?
• What is the difference between “*” and “Any” in generics
• What is enum?
• What do you know about operator overloading?
• What do you know about type aliases?
• What do you know about functional interfaces?
• What is the difference between functional interfaces and type aliases?
• What do you know about Rich Errors?

Classes

• What do you know about data classes?
• What do you know about sealed classes and interfaces?
• What do you know about inline classes?

Keywords

• What do you know about the object keyword?
• What do you know about data objects?
• What do you know about inline keyword?
• What do you know about crossinline keyword?
• What do you know about reified keyword?
• What do you know about const keyword?
• What do you know about lateinit keyword?
• What is the difference between lazy and lateinit?
• What do you know about property references and :: operator?

Structured concurrency

• What are coroutines?
• What is the difference between suspending and blocking?
• What's difference between launch and async?
• What do you know about Channels?
• What do you know about Flow?
• What do you know about StateFlow and SharedFlow?
• What is CoroutineScope and how is that different from CoroutineContext?

Collections

• What do you know about collections?
• val mutableList vs var immutableList. When to use which one?
• What is the difference between fold and reduce?
• What is the difference between map and flatMap?

Code

• Code questions