Search icon CANCEL
Arrow left icon
Explore Products
Best Sellers
New Releases
Books
Videos
Audiobooks
Learning Hub
Conferences
Free Learning
Arrow right icon
Arrow up icon
GO TO TOP
Programming Kotlin

You're reading from   Programming Kotlin Get to grips quickly with the best Java alternative

Arrow left icon
Product type Paperback
Published in Jan 2017
Publisher Packt
ISBN-13 9781787126367
Length 420 pages
Edition 1st Edition
Languages
Arrow right icon
Authors (2):
Arrow left icon
Stefan Bocutiu Stefan Bocutiu
Author Profile Icon Stefan Bocutiu
Stefan Bocutiu
Stephen Samuel Stephen Samuel
Author Profile Icon Stephen Samuel
Stephen Samuel
Arrow right icon
View More author details
Toc

Table of Contents (14) Chapters Close

Preface 1. Getting Started with Kotlin FREE CHAPTER 2. Kotlin Basics 3. Object-Oriented Programming in Kotlin 4. Functions in Kotlin 5. Higher Order Functions and Functional Programming 6. Properties 7. Null Safety, Reflection, and Annotations 8. Generics 9. Data Classes 10. Collections 11. Testing in Kotlin 12. Microservices with Kotlin 13. Concurrency

Objects and companions

We can even get a reference to objects or companion objects through reflection. For example, take the following definition of a class and a companion object:

    class Aircraft(name: String, manufacturer: String, capacity: Int)  { 
      companion object { 
        fun boeing(name: String, capacity: Int) = Aircraft(name,  "Boeing", capacity) 
      } 
    } 

Given this, we can retrieve a reference to the companion object using the appropriately named companionObject property defined on the KClass type:

    val kclass = Aircraft::class 
    val companionKClass = kclass.companionObject 

From then on, we have another KClass instance, this one modeling the functions and members of the companion object.

In fact, using the companionObjectInstance property, we can even get a handle to the instance of the companion object. Then, we could invoke functions or access properties on it directly if we cast to the appropriate type:

    val kclass = Aircraft::class 
    val...
lock icon The rest of the chapter is locked
Register for a free Packt account to unlock a world of extra content!
A free Packt account unlocks extra newsletters, articles, discounted offers, and much more. Start advancing your knowledge today.
Unlock this book and the full library FREE for 7 days
Get unlimited access to 7000+ expert-authored eBooks and videos courses covering every tech area you can think of
Renews at €18.99/month. Cancel anytime