Kotlin Tutorial for Beginners: The Kotlin Programming Language Full 9-hour Kotlin Course

This is a full length Kotlin Programming Course for beginners.

Over 9 hours of instruction that will take you from an absolute beginner to being able to write Kotlin and contribute to Kotlin projects.

This is the most comprehensive Kotlin course on YouTube.

🌟 Table of Contents 🌟
0:00 Welcome
0:02:07 Installing IntelliJ
0:03:20 Creating your First Kotlin File
0:04:38 Updating the Kotlin Plugin
0:05:43 Hello World
0:06:49 Creating a Variable
0:10:06 Creating a Read only Variable
0:12:19 Providing a Type on a Variable
0:14:00 Basic Types: Numbers
0:21:14 Basic Types: String and Char
0:24:11 String Interpolation and Triple Quotes
0:29:26 Basic Types: Boolean
0:31:18 If/Else Conditionals
0:36:25 One Line If/Else Conditional
0:40:17 Understanding Truth Tables
0:46:08 Structural Equality
0:48:19 Referential Equality
0:50:46 Nullable Types
0:52:12 Nullable Safe Calls
0:55:48 The Elvis Operator
0:57:49 Your First Kotlin Function
1:03:29 Functions with Return Types
1:08:49 Functions inside of Functions
1:11:51 Single Line Expressions
1:15:59 Function Arguments
1:21:49 Named Parameters
1:26:14 Default Function Arguments
1:30:44 IDE Refactoring to New LInes and Named Arguments
1:32:13 Multiple Args with varargs
1:34:57 Function Overloading
1:38:30 Creating your First Kotlin Class
1:45:31 Class Primary Constructors
1:49:18 Multiple Class Constructors
1:57:18 Constructor Init Blocks
2:00:57 Class Properties
2:04:00 Read Class Properties
2:04:54 Overriding a Property Getter
2:06:35 Overriding a Property Setter
2:09:42 Multiple Properties in a Class
2:11:11 Class Functions
2:15:51 Companion Objects
2:21:32 How to Create a Singleton
2:29:09 Declaring Constants
2:36:09 The lateinit modifier
2:40:23 How to Nest Classes
2:43:57 Inner Classes
2:46:56 Creating an Enum
2:51:36 Enum Constructor Parameters
2:55:27 Abstract Functions in Kotlin
2:58:51 Iterating over Enum Values
3:00:04 Adding Static Methods to Enums
3:01:37 The When Statement (Kotlin Switch Statement)
3:08:19 Exhaustive vs Non-Exhaustive When
3:15:09 Data Classes
3:19:27 Data Class with Parameterless Constructor
3:20:40 Data Class: Component1-N functions
3:24:15 Destructuring Data Classes
3:27:47 Copying Data Class Instances
3:31:17 The Pair and Triple Data Classes
3:33:50 Protected Modifier for Variables
3:40:53 Protected Modifier for Functions
3:47:02 Internal Modifier for Classes
3:55:07 Abstract Classes
3:59:45 Implementing an Abstract Class
4:13:30 Understanding Abstractions with Abstract Classes
4:17:52 What interfaces are used for
4:26:28 Creating an Interface
4:27:32 Implementing an Interface
4:28:51 Real World Interface Example
4:35:39 Anonymous Interfaces
4:40:34 Creating Arrays
4:47:06 Creating Immutable Lists
4:52:46 Creating Mutable Lists
5:00:47 Filtering a List
5:06:28 Finding Items in a List
5:12:44 Using "filterNot" on a List
5:14:10 filterTo and filterNotTo on Lists
5:16:40 Flattening Lists and Arrays
5:19:39 Combining Immutable Lists
5:21:21 List vs Map
5:29:40 Map vs FlatMap
5:34:15 Set Data Structure (a List with no Duplicates)
5:39:05 For Loops
5:44:13 While Loops
5:47:59 For Each Loops
5:51:03 Combining Lists with the Union Operator
5:53:53 Iterating over a List with an Index
5:55:28 Ranges
5:56:59 Immutable Maps
6:00:49 Mutable Maps
6:08:29 Filtering and Transforming Maps
6:16:30 Using mapNotNull on a Map
6:20:22 Generating Large Sequences
6:23:11 Measuring Performance
6:31:33 Kotlin Sequences
6:44:19 List vs Set vs Map vs Sequence
6:49:25 Kotlin Ternary Operator: Single Line If
6:50:51 Double Bang !! Operator
6:54:58 Using requireNotNull()
6:59:04 Using checkNotNull()
7:01:05 Filtering a List with filterNotNull()
7:02:20 Type Checking with 'is'
7:08:52 Casting
7:11:36 Safe Casting with 'as'
7:14:58 Generic Lists and Maps
7:19:50 Your First Generic Class
7:27:06 Throwing Exceptions
7:29:54 Creating a Custom Exception
7:32:44 Catching Exceptions with Try/Catch
7:36:09 Catching Multiple Exception Types
7:40:43 Try/Catch/Finally blocks
7:44:52 Try/Catch vs Try/Finally
7:47:27 Creating a typealias
7:50:38 Extension Functions
7:59:14 Lazy Evaluation
8:02:26 Lazy Initializer Block
8:05:42 Packages and Imports
8:14:04 Type Inference
8:21:09 Simple Lambda Expressions
8:34:29 Lambdas as Function Parameters
8:40:23 Passing Values to Lambda Function Parameters
8:51:37 Underscore Parameters in Lamba Functions
8:54:24 The 'it' Paramter in Lambda Functions
8:56:38 Calling Kotlin from Java
8:59:39 Calling Java from Kotlin
9:04:51 Calling an Extension Function from Java
9:07:50 @JvmName Annotation
9:10:21 Top Level Main Functions
9:11:15 Kotlin REPL
9:13:52 Project: Setup
9:15:54 Project: Reading Input
9:20:16 Project: Calculator Logic
9:28:04 Project: Adding Validation
9:35:54 Project: Compiling to a Jar File and Execution
9:38:21 Kotlin Koans
9:40:09 Congratulations

[donnfelkeryt]

English subtitles have just been added. Enjoy!

[fabricethilaw]

I have been using Kotlin (Android) for more than 3 years .
And this courses are just nice to watch.
You make it enjoyable to relearn the fundamentals. Great !

[robkremers]

I have just now finished the course and it's by far the most comprehensive course with regards to the Kotlin basics I have seen. Thanks Donn, for putting all the effort into making this course!

[ReetaDevi-qtur]

i am 13yrs old and i am love with this course thank you so much for making such amazing course

[alancx]

Awesome Donn, thank you so much for making this video! All the best ;)

[nguyenminhrelex]

I come from Vietnam and i learned your kotlin, you teach very good. Thank you.

[theophiluschidiebereokoye]

Just finished ! Learnt a lot of new things, awesome explanations. Thanks

[airilsra]

in the olden days we'd need to pay fortune to get this kind of course. thank you.

[major_cruze]

Thank you for the great video. Very easy and quick way to understand basics!

[AndyMyers]

Thanks for this, I made it all the way though 9 hours over about a week. I had genuinely forgotten what you looked like by the end of it; was strange to be reminded again at the end lol.

[rohonhaque]

I have learned everything to get started with Kotlin and I am here to say Thank you..❤️❤️

[jimbothebimbo]

Incredible tutorial, thank you so much! I appreciate you taking the time to answer people's queries on the individual videos as well.

[samwise]

Wow! Such a high quality for a free course with subtitles! Just can't express what a great job you did!

[ThePujjwal]

Thank you Donn. Took me some time but finally completed the 9 hrs tutorial. Looking forward for your video on co-routines.

[wareesha]

thank you so much for this effort!!! ✨

[pauliusvaitkevicius]

A very nice fundamentals course! I really liked how you explained the purpose of interfaces, the customer-menu-restaurant example is really genius :) Thank you!

[tejaspatil]

Wonderful course indeed makes difficult concepts easy

[osternosousa]

Just Finished! Really the best and most comprehensive. Best fun of the last 3 weeks of my life.

[DevilsAreRed]

Thank you for sharing your knowledge to help beginners like myself learn. Highly looking forward to future videos.

[romansinicyn]

Just finished the video. Was watching it in during breaks in-between Atomic Kotlin book.
You're a great teacher and mentor, Donn! Thank you for sharing. Really glad that I found your YouTube channel)