Kotlin Tutorial (original) (raw)

Last Updated : 06 Aug, 2025

This Kotlin tutorial is designed for beginners as well as professional, which covers basic and advanced concepts of Kotlin programming language. In this Kotlin tutorial, you'll learn various important Kotlin topics, including data types, control flow, functions, object-oriented programming, collections, and more. We will also delve into advanced concepts such as Kotlin coroutines, null safety, and functional programming in Kotlin.

Prerequisites

To get started with Kotlin, it's helpful to have a foundation in several key areas. Here are the primary prerequisites for beginners:

• **Basic Understanding of Java: Kotlin is designed to be compatible with Java, so having a basic understanding of Java programming language is recommended.
• **Programming Environment: Familiarity with any programming environment is assumed.
• **Basic Concepts : Knowledge of basic concepts such as variables, commands, syntax, etc. is assumed.
• **Basic Understanding of IDEs: Familiarity with Integrated Development Environments (IDEs) like IntelliJ IDEA or Android Studio will help you navigate and use these tools effectively.

What is Kotlin?

Kotlin is a modern programming language created by JetBrains, in 2011 the same company behind the popular IntelliJ IDEA. It runs on the Java Virtual Machine (JVM) and can also be compiled to JavaScript or native code. Kotlin is an object-oriented language, and a “better language” than Java, but still be fully interoperable with Java code. Kotlin is sponsored by Google, announced as one of the official languages for Android Development in 2017.

Why Kotlin for Android Development?

• **Google Support: Kotlin is officially supported by Google for Android development, ensuring it works well with Android Studio.
• **Easy to Read and Write : Kotlin’s code is shorter and clearer than Java, making it easier to understand and work with.
• **Works with Java: Kotlin can be used with Java in the same project, making it easy to switch from Java to Kotlin.
• **Null Safety: Kotlin helps avoid errors by clearly handling null values, which are a common source of bugs in Java.
• **Better Asynchronous Code: Kotlin’s coroutines make it easier to handle background tasks like network requests without blocking the app.
• **Strong Community: Kotlin has a growing number of libraries, tools, and community resources to support developers.

Overview

• Introduction to Kotlin
• Kotlin Environment setup for Command Line
• Kotlin Environment setup with Intellij IDEA
• Hello World program in Kotlin

Basics

• Kotlin Data Types
• Kotlin Variables
• Kotlin Operators
• Kotlin Standard Input/Output
• Kotlin Type Conversion
• Kotlin Expression, Statement and Block

**Control Flow

• Kotlin if-else expression
• Kotlin while loop
• Kotlin do-while loop
• Kotlin for loop
• Kotlin when expression
• Kotlin Unlabeled break
• Kotlin labeled break
• Kotlin unlabeled continue
• Kotlin labeled continue

**Array & String

• Kotlin Array
• Kotlin String

**Functions

• Kotlin functions
• Kotlin | Default and Named argument
• Kotlin Recursion
• Kotlin Tail Recursion
• Lambdas Expressions and Anonymous Functions
• Kotlin Inline functions
• Kotlin infix function notation
• Kotlin Higher-Order Functions

Collections

• Kotlin Collections
• Kotlin list : Arraylist
• Kotlin list : listOf()
• Kotlin Set : setOf()
• Kotlin mutableSetOf()
• Kotlin hashSetOf()
• Kotlin Map : mapOf()
• Kotlin Hashmap

**OOPs Concept

• Kotlin Class and Objects
• Kotlin Nested class and Inner class
• Kotlin Setters and Getters
• Kotlin | Class Properties and Custom Accessors
• Kotlin Constructor
• Kotlin Visibility Modifiers
• Kotlin Inheritance
• Kotlin Interfaces
• Kotlin Data Classes
• Kotlin Sealed Classes
• Kotlin Abstract class
• Enum classes in Kotlin
• Kotlin extension function
• Kotlin generics

Exception Handling

• Kotlin Exception Handling | try, catch, throw and finally
• Kotlin Nested try block and multiple catch block

**Null Safety

• Kotlin Null Safety
• Kotlin | Type Checking and Smart Casting
• Explicit type casting

**Regex & Ranges

• Kotlin Regular Expression
• Kotlin Ranges

**Java Interoperability

• Java Interoperability – Calling Kotlin from Java
• Java Interoperability – Calling Java from Kotlin

Miscellaneous

• Kotlin annotations
• Kotlin Reflection
• Kotlin Operator Overloading
• Destructuring Declarations in Kotlin
• Equality evaluation in Kotlin
• Comparator in Kotlin
• Triple in Kotlin
• Pair in Kotlin
• Kotlin | apply vs with

Android

• Kotlin Android Tutorial
• How to create project in Android Studio using Kotlin
• How to install Android Virtual Device(AVD)
• Android Animations in Kotlin
• Android Fade In/Out in Kotlin
• Android Menus
• Android progress notifications in Kotlin
• Android Project folder Structure

Conclusion

In this Kotlin tutorial, we’ve explored the key features and benefits of using Kotlin for Android development. From its concise and readable syntax to its seamless interoperability with Java, Kotlin offers numerous advantages that make it an excellent choice for both new and experienced developers. We’ve also highlighted Kotlin’s null safety, which helps prevent common programming errors, and its powerful coroutines for managing asynchronous tasks efficiently.