To install JDK 21 and Visual Studio Code to write and run a “Hello World” Java program, you can follow these detailed steps:

Step 1: Install JDK 21

  1. Download JDK 21:
    • Go to the official Oracle website or an OpenJDK version provider.
    • Find JDK 21 and download the installer for your operating system (Windows, macOS, or Linux).
  2. Install JDK 21:
    • Windows:
      • Run the downloaded installer.
      • Follow the installation prompts. Make sure to note the installation path.
      • Add JDK to the PATH environment variable:
        • Search for “Environment Variables” in the Start menu.
        • Click on “Edit the system environment variables.”
        • In the “System Properties” window, click on “Environment Variables.”
        • Under “System Variables,” find and select the “Path” variable, then click “Edit.”
        • Click “New” and add the JDK bin folder path (e.g., C:\Program Files\Java\jdk-21\bin).
        • Click “OK” to close all dialogs.
    • macOS/Linux:
      • Open Terminal.
      • Change to the directory containing the downloaded installer.
      • Run the installer using the appropriate command. For macOS, it might be a .dmg file that you can simply open and follow the prompts. For Linux, you might use a package manager or run an installer script.
  3. Verify Installation:
    • Open a terminal or command prompt.
    • Type java -version and press Enter.
    • If JDK 21 is correctly installed, you should see the version number displayed.

Step 2: Install Visual Studio Code

  1. Download Visual Studio Code:
    • Visit the official Visual Studio Code website (code.visualstudio.com).
    • Download the version for your operating system.
  2. Install Visual Studio Code:
    • Windows/macOS: Run the downloaded installer and follow the prompts.
    • Linux: Follow the specific instructions for your distribution on the Visual Studio Code website.
  3. Install Java Extension Pack:
    • Open Visual Studio Code.
    • Go to the Extensions view by clicking on the square icon on the sidebar or pressing Ctrl+Shift+X.
    • Search for “Java Extension Pack” by Microsoft and install it. This pack includes essential tools for Java development.

Step 3: Write and Run a “Hello World” Java Program

  1. Create a New Java Project:
    • Open Visual Studio Code.
    • Click on “File” > “New File”.
    • Save the file with a .java extension, for example, HelloWorld.java, in a new folder.
  2. Write the Hello World Program:
    • Type the following code into the new file:javaCopy codepublic class HelloWorld { public static void main(String[] args) { System.out.println("Hello, World!"); } }
    • Save the file (Ctrl+S).
  3. Run the Program:
    • Right-click in the text editor window and select “Run Java.”
    • Alternatively, press F5 to run the program.
    • The output “Hello, World!” should appear in the terminal or output window in Visual Studio Code.

Refer video @ https://youtu.be/mpd21PugirQ