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Introduction to Kotlin

Why Kotlin?
  • Java have so much boilerplate code.
  • Some other languages has performance issues. 
  • Kotlin is statically typed language that runs on the Java virtual machine and also can be compiled to JavaScript source code.
  • Inspired by Java, Scala, C# and Groovy.
  • Kotlin develop such a way that it can be use for any type of application such as web, Desktop,  Server-side. But it's adopted heavily in Android. 
  • Interoperability allows gradual adoption. So no need to change whole codebase into Kotlin.
  • Gradle has adopted Kotlin for it’s scripting and plugins. Gradle using Groovy for scripting and plugins.
  • In Kotlin everything is an object.
  • Two ways to declare variables in Kotlin : var for mutable and val is for immutable.

These are some of the plus points of this language. So let's dive into this language.

 Kotlin programs start at the main function. When targeting JVM, function will be compiled as a static method.
To save file as a kotlin file you need to add .kt extension to file name. 

Let's look into var and val example.


Let's see another example of how to use multilines in Kotlin.

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