How to work with nested class

In this recipe, we will see how to use nested classes in Kotlin. A nested class is a member of its enclosing class.

Getting ready

You need to install a preferred development environment that compiles and runs Kotlin. You can also use the command line for the purpose, for which you need Kotlin compiler installed along with JDK. I am using online IDE at https://try.kotlinlang.org/ to compile and run my Kotlin code for this recipe.

How to do it...

Now we will see how to work with a nested class in the following steps:

1. Let's try an example of a nested class in Kotlin:

fun main(args: Array<String>) {
    var a1 = outCl()
    a1.printAB()
    outCl.inCl().printB()
}
class outCl {
var a = 6
    fun printAB () {
    var b_ = inCl().b
    println ("a = $a and b = $b_ from inside outCl")
}

class inCl {
    var b = "9"
        fun printB() {
            println ("b = $b from inside inCl")
        }
    }
}

Here's the output:

a = 6 and b = 9 from inside outCl
b = 9 from...