1. Choose JDK Version and Vendor

Popular JDK vendors:

• Oracle JDK – official version

• OpenJDK – open-source

• Amazon Corretto, Azul Zulu, Adoptium – alternative builds

 For most purposes, Adoptium Temurin or Oracle JDK is recommended.

 Windows Installation

Option 1: Using Oracle JDK

1. Go to: https://www.oracle.com/java/technologies/javase-downloads.html

2. Select the version (e.g., Java 17 or Java 21 LTS).

3. Download the .exe installer.

4. Run the installer and follow the prompts.

5. Verify installation:
   Open Command Prompt and run:

   java -version
   javac -version
   

Option 2: Using Adoptium (OpenJDK)

1. Go to: https://adoptium.net/

2. Choose a version (e.g., Java 17) and Windows OS.

3. Download the MSI Installer.

4. Install and follow prompts.

5. Confirm with:

   java -version
   

 macOS Installation

Option 1: Oracle JDK

1. Go to https://www.oracle.com/java/technologies/javase-downloads.html

2. Download the macOS .dmg installer.

3. Open and run the installer.

4. To verify:

   java -version
   

Option 2: Using Homebrew (Recommended for developers)

1. Open Terminal.

2. Run:

   brew install openjdk@17
   

3. Add Java to your PATH:

   echo 'export PATH="/opt/homebrew/opt/openjdk@17/bin:$PATH"' >> ~/.zprofile
   source ~/.zprofile
   

4. Verify:

   java -version
   

 Linux Installation (Ubuntu/Debian)

Option 1: Default JDK from Repository

sudo apt update
sudo apt install default-jdk -y

Option 2: Install Specific Version (e.g., OpenJDK 17)

sudo apt install openjdk-17-jdk -y

Verify Installation:

java -version
javac -version

 After Installation

1. Set JAVA_HOME (Optional but useful):

   • On Windows: Set Environment Variable JAVA_HOME to the JDK path (e.g., C:\Program Files\Java\jdk-17)

   • On Linux/macOS:

     export JAVA_HOME=$(dirname $(dirname $(readlink -f $(which java))))
     export PATH=$JAVA_HOME/bin:$PATH
     

2. IDE Integration: Install an IDE like IntelliJ IDEA, Eclipse, or VS Code with Java extensions.