Book Image

Mastering Kotlin

By : Nate Ebel
Book Image

Mastering Kotlin

By: Nate Ebel

Overview of this book

Using Kotlin without taking advantage of its power and interoperability is like owning a sports car and never taking it out of the garage. While documentation and introductory resources can help you learn the basics of Kotlin, the fact that it’s a new language means that there are limited learning resources and code bases available in comparison to Java and other established languages. This Kotlin book will show you how to leverage software designs and concepts that have made Java the most dominant enterprise programming language. You’ll understand how Kotlin is a modern approach to object-oriented programming (OOP). This book will take you through the vast array of features that Kotlin provides over other languages. These features include seamless interoperability with Java, efficient syntax, built-in functional programming constructs, and support for creating your own DSL. Finally, you will gain an understanding of implementing practical design patterns and best practices to help you master the Kotlin language. By the end of the book, you'll have obtained an advanced understanding of Kotlin in order to be able to build production-grade applications.
Table of Contents (25 chapters)
Free Chapter
1
Section 1: Kotlin – A Modern Solution to Application Development
4
Section 2: Putting the Pieces Together – Modeling Data, Managing State, and Application Architecture
8
Section 3: Play Nice – Integrating Kotlin With Existing Code
13
Section 4: Go Beyond – Exploring Advanced and Experimental Language Features
17
Section 5: The Wide World of Kotlin – Using Kotlin across the Entire Development Stack

Understanding data classes

We often create classes that are meant to hold data and nothing else. In these cases, we may often want to override specific methods such as equals() and hashCode() so these data classes can be compared to one another. In Kotlin, this type of class is supported natively.

Creating a data class

To create a data class, we can add the data keyword to a class declaration as long as the class follows several specific rules:

  • It is a primary constructor with at least one property
  • It cannot be a sealed class, open, inner, or abstract

In this example, we define a data class, Article, which contains two primary constructor properties:

data class Article(val title: String, val author: String)

Primary constructor...