Getting Started

This chapter will guide you through setting up a streamlined Java development environment using Visual Studio Code (VS Code). By the end of this section, you will have a fully functional Java Development Kit (JDK), a VS Code installation, and the necessary extensions for a productive coding experience, including compiling and debugging.

1. Install Visual Studio Code

The first step is to install Visual Studio Code. You can download it from the official website at https://code.visualstudio.com/. Follow the installation instructions tailored to your operating system.

• For Windows, this involves running the downloaded .exe installer.
• On macOS, you will drag the VS Code application into your Applications folder.
• For Linux users, VS Code is available through most distribution package managers.

2. Install the Java Development Kit (JDK)

To compile and run Java code, you need a Java Development Kit (JDK). You have the choice between Oracle JDK and OpenJDK, which is an open-source alternative favored by most developers. We recommend the OpenJDK builds from Adoptium, available at https://adoptium.net/.

Alternatively, you can find the Oracle JDK at https://www.oracle.com/java/technologies/downloads/.

The installation process varies by operating system.

Follow the provider instructions to install the JDK on your operating system.

To confirm that the JDK was installed correctly, open a terminal and execute the command java -version. You should see output that displays the JDK version:

openjdk version "21.0.8" 2025-07-15
OpenJDK Runtime Environment (Red_Hat-21.0.8.0.9-1) (build 21.0.8+9)
OpenJDK 64-Bit Server VM (Red_Hat-21.0.8.0.9-1) (build 21.0.8+9, mixed mode, sharing)

3. Set up Java in VS Code

With both VS Code and the JDK installed, the next step is to configure VS Code for Java development by adding extensions.

The most important is the Extension Pack for Java by Microsoft. This pack provides comprehensive support for Java, including language support, debugging, testing, and integration with build tools like Maven and Gradle. To install it, open the Extensions view in VS Code (with Ctrl+Shift+X or Cmd+Shift+X), search for "Extension Pack for Java", and click "Install".

4. Create a Simple Java Program

To verify that your setup is working, let's create a simple "Hello, World!" program. In VS Code, create a new folder named hello-java and, within it, a file named HelloWorld.java. Add the following code to the file:

public class HelloWorld {
    public static void main(String[] args) {
        System.out.println("Hello, World!");
    }
}

You can run this program directly in VS Code by pressing Ctrl+F5.

Alternatively, you can open a terminal within the hello-java folder and run the commands javac HelloWorld.java to compile the code, followed by java HelloWorld to execute it. In either case, you should see the output "Hello, World!" printed to the console.