How to Install Kotlin: Step-by-Step Guide for Beginners

To install Kotlin, download and install the official Kotlin compiler from the Kotlin website or use an IDE like IntelliJ IDEA which has Kotlin built-in. You can also install Kotlin via SDKMAN! on Linux/macOS or use package managers like Homebrew on macOS.

Syntax

Installing Kotlin involves setting up the Kotlin compiler or an IDE that supports Kotlin. The main parts are:

• Kotlin Compiler: The command-line tool to compile Kotlin code.
• IDE: Software like IntelliJ IDEA that helps write and run Kotlin easily.
• Package Manager: Tools like SDKMAN! or Homebrew to install Kotlin automatically.

bash

kotlinc HelloWorld.kt -include-runtime -d HelloWorld.jar
java -jar HelloWorld.jar

Example

This example shows how to install Kotlin using SDKMAN! on macOS or Linux, then compile and run a simple Kotlin program.

bash

# Install SDKMAN!
curl -s "https://get.sdkman.io" | bash
source "$HOME/.sdkman/bin/sdkman-init.sh"

# Install Kotlin
sdk install kotlin

# Create a Kotlin file
cat <<EOF > HelloWorld.kt
fun main() {
    println("Hello, Kotlin!")
}
EOF

# Compile Kotlin code
kotlinc HelloWorld.kt -include-runtime -d HelloWorld.jar

# Run the program
java -jar HelloWorld.jar

Output

Hello, Kotlin!

Common Pitfalls

Some common mistakes when installing Kotlin include:

• Not setting the PATH environment variable to include Kotlin compiler binaries.
• Trying to run Kotlin code without compiling it first.
• Using outdated Kotlin versions or incompatible Java versions.
• Not installing Java Development Kit (JDK) which Kotlin needs to run.

Always ensure you have a compatible JDK installed and your environment variables are set correctly.

bash

## Wrong: Trying to run Kotlin source directly without compiling
kotlin HelloWorld.kt

## Right: Compile then run
kotlinc HelloWorld.kt -include-runtime -d HelloWorld.jar
java -jar HelloWorld.jar

Quick Reference

Step	Command / Action
Install JDK	Download and install JDK 8 or higher from Oracle or OpenJDK
Install Kotlin Compiler	Use SDKMAN!: sdk install kotlin or download from kotlinlang.org
Set PATH	Add Kotlin compiler bin directory to your system PATH
Write Kotlin Code	Create a file with .kt extension
Compile Kotlin Code	kotlinc filename.kt -include-runtime -d output.jar
Run Kotlin Program	java -jar output.jar
Use IDE	Install IntelliJ IDEA for built-in Kotlin support

Key Takeaways

Install a compatible JDK before installing Kotlin.

Use SDKMAN! or package managers for easy Kotlin installation.

Set your PATH environment variable to run Kotlin commands from anywhere.

Compile Kotlin code before running it with the Java command.

IntelliJ IDEA is the easiest way to start coding in Kotlin.