Java Setup 2025

The basic Github Codespaces image has Java built into it. If you are already using a Codespace, skip to the “Check Java” section.

Java Starter Repository

If you already have a codespace, you can skip this section.

To set up a new codespace, find with Github’s blank template and select “Use this template” to open it in a codespace. You can skip all of the configuration options.

Install Code Runner

Code Runner is a simplified way of running programs.

On the left side, find the Extensions (Control-Shift-X), and search for “Code Runner”. Install it. Open the Settings (gear icon). I recommend selecting the following:

Ignore Selection
Save All Files Before Run
Save File Before Run

Check Java

Make a new Java file: “New file…” and call it Practice.java.

Include the following text:

  public class Practice {
      public static void main (String[] args) {
          System.out.println("Yes, this works.");
      }
  }

Save (Control-S) and run with the Code Runner “Play” icon or Control-Alt-N keyboard shortcut.