Book Image

Kotlin Quick Start Guide

By : Marko Devcic
Book Image

Kotlin Quick Start Guide

By: Marko Devcic

Overview of this book

Kotlin is a general purpose, object-oriented language that primarily targets the JVM and Android. Intended as a better alternative to Java, its main goals are high interoperability with Java and increased developer productivity. Kotlin is still a new language and this book will help you to learn the core Kotlin features and get you ready for developing applications with Kotlin. This book covers Kotlin features in detail and explains them with practical code examples.You will learn how to set up the environment and take your frst steps with Kotlin and its syntax. We will cover the basics of the language, including functions, variables, and basic data types. With the basics covered, the next chapters show how functions are first-class citizens in Kotlin and deal with the object-oriented side of Kotlin. You will move on to more advanced features of Kotlin. You will explore Kotlin's Standard Library and learn how to work with the Collections API. The book finishes by putting Kotlin in to practice, showing how to build a desktop app. By the end of this book, you will be confident enough to use Kotlin for your next project.
Table of Contents (15 chapters)
Title Page
Copyright and Credits
Packt Upsell


A Kotlin class doesn't have setter or getter methods, yet it doesn't break encapsulation by exposing private fields. The reason is that Kotlin has properties. C# is one of the languages Kotlin drew inspiration from, and the concept of properties is one of the things it took from C#. You can think of properties as fields and methods, all in one place. To the outside users of a property, the syntax looks like they are accessing a public field of a class. Internally in your class, behind a property, you can have get and set accessors or methods and a private backing field. The get and set methods then control how your private field is accessed, thus not breaking encapsulation.

Specifying get and set, as in our case, is optional. If you omit them, then it is implied that the property is both read and write. The compiler generates a private backing field for you in that case. You can also have get only accessor inside a property. This is then considered a read-only property and it cannot...