Part 3: OOP & Functions

Model your domain with Kotlin’s object-oriented and function features.

What You’ll Learn

• Classes, constructors, properties, and visibility
• Inheritance, interfaces, and abstract classes
• data, enum, and sealed classes with exhaustive when
• Objects, companion objects, and singletons
• Extension functions and advanced function features

Chapters

Chapter	Description
Classes & Properties	Constructors, properties, accessors, lazy
Visibility & Packages	Modifiers, packages, imports
Inheritance & Interfaces	open/override, abstract, interfaces
Data, Enum & Sealed Classes	data/enum/sealed + exhaustive when
Objects & Companions	object, companion object, singletons
Extension Functions	Extension functions, infix, vararg

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Table of contents

• Classes & Properties
• Visibility & Packages
• Inheritance & Interfaces
• Data, Enum & Sealed Classes
• Objects & Companions
• Extension Functions