Kotlin Programming by Skeen, Josh -- Read -- Imperial Library of Trantor

Index

Cover Page Title Page Dedication Acknowledgments Table of Contents Introducing Kotlin

Why Kotlin? Who Is This Book For? How to Use This Book

For the More Curious Challenges Typographical conventions Using an eBook

Looking Forward

1. Your First Kotlin Application

Installing IntelliJ IDEA Your First Kotlin Project

Creating your first Kotlin file Running your Kotlin file

Compilation and execution of Kotlin/JVM code

The Kotlin REPL For the More Curious: Why Use IntelliJ? For the More Curious: Targeting the JVM Challenge: REPL Arithmetic

2. Variables, Constants, and Types

Types Declaring a Variable Kotlin’s Built-In Types Read-Only Variables Type Inference Compile-Time Constants Inspecting Kotlin Bytecode For the More Curious: Java Primitive Types in Kotlin Challenge: hasSteed Challenge: The Unicorn’s Horn Challenge: Magic Mirror

3. Conditionals

if/else Statements

Adding more conditions Nested if/else statements More elegant conditionals

Logical operators Conditional expressions Removing braces from if/else expressions

Ranges when Expressions String Templates Challenge: Trying Out Some Ranges Challenge: Enhancing the Aura Challenge: Configurable Status Format

4. Functions

Extracting Code to Functions Anatomy of a Function

Function header

Visibility modifier Function name declaration Function parameters Function return type

Function body Function scope

Calling a Function Refactoring to Functions Writing Your Own Functions Default Arguments Single-Expression Functions Unit Functions Named Function Arguments For the More Curious: The Nothing Type For the More Curious: File-Level Functions in Java For the More Curious: Function Overloading For the More Curious: Function Names in Backticks Challenge: Single-Expression Functions Challenge: Fireball Inebriation Level Challenge: Inebriation Status

5. Anonymous Functions and the Function Type

Anonymous Functions

The function type Implicit returns Function arguments The it keyword Accepting multiple arguments

Type Inference Support Defining a Function That Accepts a Function

Shorthand syntax

Function Inlining Function References Function Type as Return Type For the More Curious: Kotlin’s Lambdas Are Closures For the More Curious: Lambdas vs Anonymous Inner Classes

6. Null Safety and Exceptions

Nullability Kotlin’s Explicit Null Type Compile Time vs Runtime Null Safety

Option one: the safe call operator

Using safe calls with let

Option two: the double-bang operator Option three: checking whether a value is null with if

The null coalescing operator

Exceptions

Throwing an exception Custom exceptions Handling exceptions

Preconditions Null: What Is It Good For? For the More Curious: Checked vs Unchecked Exceptions For the More Curious: How Is Nullability Enforced?

7. Strings

Extracting Substrings

substring split

String Manipulation

Strings are immutable

String Comparison For the More Curious: Unicode For the More Curious: Traversing a String’s Characters Challenge: Improving DragonSpeak

8. Numbers

Numeric Types Integers Decimal Numbers Converting a String to a Numeric Type Converting an Int to a Double Formatting a Double Converting a Double to an Int For the More Curious: Bit Manipulation Challenge: Remaining Pints Challenge: Handling a Negative Balance Challenge: Dragoncoin

9. Standard Functions

apply let run with also takeIf

takeUnless

Using Standard Library Functions

10. Lists and Sets

Lists

Accessing a list’s elements

Index boundaries and safe index access Checking the contents of a list

Changing a list’s contents

Iteration Reading a File into a List Destructuring Sets

Creating a set Adding elements to a set

while Loops The break Expression Collection Conversion For the More Curious: Array Types For the More Curious: Read-Only vs Immutable Challenge: Formatted Tavern Menu Challenge: Advanced Formatted Tavern Menu

11. Maps

Creating a Map Accessing Map Values Adding Entries to a Map Modifying Map Values Challenge: Tavern Bouncer

12. Defining Classes

Defining a Class Constructing Instances Class Functions Visibility and Encapsulation Class Properties

Property getters and setters Property visibility Computed properties

Refactoring NyetHack Using Packages For the More Curious: A Closer Look at var and val Properties For the More Curious: Guarding Against Race Conditions For the More Curious: Package Private

13. Initialization

Constructors

Primary constructors Defining properties in a primary constructor Secondary constructors Default arguments Named arguments

Initializer Blocks Property Initialization Initialization Order Delaying Initialization

Late initialization Lazy initialization

For the More Curious: Initialization Gotchas Challenge: The Riddle of Excalibur

14. Inheritance

Defining the Room Class Creating a Subclass Type Checking The Kotlin Type Hierarchy

Type casting Smart casting

For the More Curious: Any

15. Objects

The object Keyword

Object declarations Object expressions Companion objects

Nested Classes Data Classes

toString equals copy Destructuring declarations

Enumerated Classes Operator Overloading Exploring the World of NyetHack For the More Curious: Defining Structural Comparison For the More Curious: Algebraic Data Types Challenge: “Quit” Command Challenge: Implementing a World Map Challenge: Ring the Bell

16. Interfaces and Abstract Classes

Defining an Interface Implementing an Interface Default Implementations Abstract Classes Combat in NyetHack

17. Generics

Defining Generic Types Generic Functions Multiple Generic Type Parameters Generic Constraints vararg and get in and out For the More Curious: The reified Keyword

18. Extensions

Defining Extension Functions

Defining an extension on a superclass

Generic Extension Functions Extension Properties Extensions on Nullable Types Extensions, Under the Hood Extracting to Extensions Defining an Extensions File Renaming an Extension Extensions in the Kotlin Standard Library For the More Curious: Function Literals with Receivers Challenge: toDragonSpeak Extension Challenge: Frame Extension

19. Functional Programming Basics

Function Categories

Transforms Filters Combines

Why Functional Programming? Sequences For the More Curious: Profiling For the More Curious: Arrow.kt Challenge: Reversing the Values in a Map Challenge: Applying Functional Programming to Tavern.kt Challenge: Sliding Window

20. Java Interoperability

Interoperating with a Java Class Interoperability and Nullity Type Mapping Getters, Setters, and Interoperability Beyond Classes Exceptions and Interoperability Function Types in Java

21. Building Your First Android Application with Kotlin

Android Studio

Gradle configuration Project organization

Defining a UI Running the App on an Emulator Generating a Character The Activity Class Wiring Up Views Kotlin Android Extensions Synthetic Properties Setting a Click Listener Saved Instance State

Reading from the saved instance state

Refactoring to an Extension For the More Curious: Android KTX and Anko Libraries

22. Introduction to Coroutines

Parsing Character Data Fetching Live Data The Android Main Thread Enabling Coroutines Specifying a Coroutine with async launch vs async/await Suspending Functions Challenge: Live Data Challenge: Minimum Strength

23. Afterword

Where to Go from Here Shameless Plugs Thank You

A. More Challenges

Leveling Up with Exercism

Glossary Index

← Prev
Back
Next →

← Prev
Back
Next →