Unless you've been living on Mars (lucky you!) cut off from all forms of communication, you've heard of a new programming language, named Kotlin, that is considered the heir apparent to Java.

Developed and perfected over a five-year period by JetBrains (the company behind IntelliJ IDEA), Kotlin has taken the Java development community by storm. The new language is described as "concise," "safe," and "100% interoperable" with Java, and it runs on the Java Virtual Machine (JVM).

Kotlin has already been adopted by some big companies-including Uber, Netflix, Pinterest, and Square-as their primary language for developing Android apps. And in May of 2017, Google announced Kotlin was now a "first-class language" for writing Android apps, subsequently conducting all of its developers' conferences in it. The message is clear.

So, what's keeping you from checking out Kotlin for yourself and seeing what it can do?




What you will learn

Run a Kotlin application and understand the integration with Android Studio

Incorporate Kotlin into new/existing Android Java based project

Learn about Kotlin type system to deal with null safety and immutability

Define various types of classes and deal with properties

Define collections and transform them in functional way

Define extensions, new behaviours to existing libraries and Android framework classes

Use generic type variance modifiers to define subtyping relationship between generic types

Build a sample application

Model data using interfaces, classes, and data classes

Grapple with practical interoperability challenges and solutions with Java

Build parallel apps using concurrency solutions such as coroutines

Explore functional, reactive, and imperative programming to build flexible apps

Discover how to build your own domain-specific language

Embrace functional programming using the standard library and Arrow

Delve into the use of Kotlin for frontend javascript development

Build server-side services using Kotlin and Ktor

Java isn't the only language you can use to build Android apps. The most strongly supported JVM language in the Android ecosystem-aside from Java-is Kotlin, an open-source, statically typed language developed by JetBrains.

JetBrains created one of the most popular IDEs, IntelliJ IDEA, as well as Android Studio, which Google crowned as the standard IDE for Android development. It understood the pain developers face in day-to-day development workflow, and with Kotlin it has attempted to address those. JetBrains uses Kotlin in production to develop its own products, so it is unlikely that the language will suddenly be abandoned.

Kotlin takes a pragmatic approach by not including features such as having its own build system or package manager because open source tools such as Gradle and Maven already handle this well. Having its own build system would have broken projects that already use Gradle and Maven.

Another pragmatic approach for Kotlin was to not re-implement the entire Java collections framework. That would have been easy, but the creators also wanted Kotlin to be compatible with the JDK collection interfaces without breaking any existing project implementations.

One other huge benefit of Kotlin is that most of its language design decisions focused on maintaining backward compatibility with many Java and Android projects. For example, Kotlin still supports Java 6 bytecode because more than half Android devices still run on it.
Kotlin is 100% interoperable with Java