Installing Java on Your Computer

Windows – Java 21 (Oracle) + VS Code Setup

1️⃣ Step 1: Download and Install Oracle JDK 21

1. Go to the official Oracle page:

   🔗 https://www.oracle.com/java/technologies/javase/jdk21-archive-downloads.html

2. Scroll down → Under Windows x64 Installer, click:

   jdk-21_windows-x64_bin.exe

3. Sign in or create an Oracle account to download.

4. Run the .exe installer → Click Next → Finish.

2️⃣ Step 2: Set Environment Variables

1. Press Windows key → Search Environment Variables → Open.

2. Under System Variables:

   • Click New

     • Name: JAVA_HOME

     • Value: C:\\Program Files\\Java\\jdk-21 (or your JDK 21 path)

   • Select Path → Click Edit → Click New → Add:

     %JAVA_HOME%\\bin

3️⃣ Step 3: Verify Installation

Open Command Prompt and type:

java -version
javac -version

java version "21.0.3"  (or similar)

4️⃣ Step 4: Install VS Code

1. Download from:

   🔗 https://code.visualstudio.com/

2. Install using default settings → Open VS Code.

5️⃣ Step 5: Install Java Extensions in VS Code

1. Press Ctrl + Shift + X to open Extensions.

2. Search: Java Extension Pack

3. Click Install.

6️⃣ Step 6: Create and Run Java Program

1. Create a folder → Open it in VS Code.

2. Create a file: Hello.java

public class Hello {
    public static void main(String[] args) {
        System.out.println("Hello from Java 21 on Windows!");
    }
}

Click Run at the top or press Ctrl + F5.

macOS – Java 21 (Oracle) + VS Code Setup

1️⃣ Step 1: Download and Install Oracle JDK 21

1. Go to:

   🔗 https://www.oracle.com/java/technologies/javase/jdk21-archive-downloads.html

2. Scroll to macOS x64 or macOS AArch64 (for Apple M1/M2)

   • Download .dmg file (e.g., jdk-21_macos-aarch64_bin.dmg)

3. Open .dmg → Drag and drop Java into Applications → Done.

2️⃣ Step 2: Set JAVA_HOME

Open Terminal and run:

/usr/libexec/java_home -V

Copy the path for JDK 21, then add it to your profile (.zshrc or .bash_profile):

export JAVA_HOME=$(/usr/libexec/java_home -v 21)
export PATH=$JAVA_HOME/bin:$PATH

Then apply it:

source ~/.zshrc

3️⃣ Step 3: Verify Installation

In Terminal, type:

java -version
javac -version

java version "21.0.3"

4️⃣ Step 4: Install VS Code

1. Download from:

   🔗 https://code.visualstudio.com/

2. Drag to Applications → Open VS Code.

5️⃣ Step 5: Install Java Extensions

1. Open VS Code → Press Cmd + Shift + X

2. Search: Java Extension Pack

3. Click Install

6️⃣ Step 6: Create and Run Java Code

1. Create a folder → Open in VS Code.

2. Create Hello.java:

public class Hello {
    public static void main(String[] args) {
        System.out.println("Hello from Java 21 on Mac!");
    }
}

Click Run or press Cmd + Fn + F5