Kotlin Tutorials

Kotlin Tutorials Roadmap

Section 1: Introduction to Kotlin

  • What is Kotlin?
    • A modern, statically typed programming language.
    • Developed by JetBrains.
    • Interoperable with Java.
    • Used for Android development, server-side applications, web development, and more.
  • Setting up the Development Environment:
    • Installing IntelliJ IDEA (recommended IDE).
    • Setting up the Kotlin plugin.
    • Creating your first Kotlin project.
  • Your First Kotlin Program:
    • Understanding the main function.
    • Printing to the console.
    • Basic syntax.

Section 2: Basic Syntax and Concepts

  • Variables:
    • val (read-only) and var (mutable).
    • Type inference.
    • Explicit type declaration.
  • Data Types:
    • Numbers (Int, Long, Double, Float).
    • Booleans.
    • Characters.
    • Strings.
  • Control Flow:
    • if, else if, else expressions.
    • when expressions (similar to switch).
    • for loops.
    • while and do-while loops.
  • Functions:
    • Defining functions.
    • Function parameters and return types.
    • Single-expression functions.
    • Default and named arguments.
  • Nullable Types and Null Safety:
    • Understanding nullable types (`?`).
    • Safe call operator (`?.`).
    • Elvis operator (`?:`).
    • Non-null assertion operator (`!!`).

Section 3: Object-Oriented Programming in Kotlin

  • Classes and Objects:
    • Defining classes.
    • Creating instances of classes.
    • Constructors (primary and secondary).
    • Properties.
  • Inheritance:
    • Using the open keyword.
    • Overriding members.
  • Interfaces:
    • Defining interfaces.
    • Implementing interfaces.
    • Abstract classes.
  • Data Classes:
    • Automatic generation of equals(), hashCode(), toString(), copy().
  • Sealed Classes:
    • Restricting class hierarchies.
    • Useful with when expressions.
  • Enums:
    • Defining enumerated types.
    • Properties and methods in enums.

Section 4: Collections and Generics

  • Kotlin Collections:
    • Lists (List, MutableList).
    • Sets (Set, MutableSet).
    • Maps (Map, MutableMap).
    • Common collection operations (filtering, mapping, etc.).
  • Generics:
    • Understanding generic types.
    • Variance (in, out).

Section 5: Advanced Topics

  • Extension Functions and Properties:
    • Adding new functionality to existing classes.
  • Lambdas and Higher-Order Functions:
    • Passing functions as arguments or returning them.
    • Common higher-order functions (map, filter, reduce).
  • Coroutines:
    • Understanding coroutines for asynchronous programming.
    • Suspend functions.
    • Builders (launch, async).
    • Context and dispatchers.
  • Delegation:
    • Class delegation.
    • Delegated properties (lazy, observable).
  • Type Aliases:
    • Giving alternative names to existing types.

Section 6: Interoperability with Java

  • Calling Java Code from Kotlin:
    • Seamless integration.
    • Handling nullability from Java.
  • Calling Kotlin Code from Java:
    • Understanding generated Java code.
    • Annotations for better Java interoperability (@JvmStatic, @JvmOverloads, etc.).

Section 7: Kotlin for Specific Platforms

  • Kotlin for Android Development:
    • Using Kotlin with Android Studio.
    • Android KTX extensions.
    • Coroutines in Android.
  • Kotlin for Server-Side Development:
    • Frameworks like Ktor and Spring Boot with Kotlin.
  • Kotlin/JS for Web Development:
    • Compiling Kotlin to JavaScript.
    • Working with frontend frameworks.
  • Kotlin Native for Multiplatform Development:
    • Compiling Kotlin to native code.
    • Sharing code across platforms (iOS, desktop, etc.).

Section 8: Testing and Best Practices

  • Unit Testing:
    • Using testing frameworks (JUnit, Spek).
  • Code Style and Conventions:
    • Following Kotlin's official style guide.
  • Common Pitfalls and How to Avoid Them:
    • Understanding common mistakes and best practices.

Section 9: Real-World Projects and Resources

  • Building a simple Android application.
  • Creating a basic server-side application with Ktor.
  • Examples of multiplatform projects.
  • Learning Resources:
    • Official Kotlin documentation.
    • Kotlin Koans (interactive exercises).
    • Community blogs and GitHub projects.
    • Online courses and tutorials.