How to Use VSCode with MOOC.fi Java Course (Instead of NetBeans)

Mar 18, 2026

The Problem

I wanted to take the University of Helsinki’s MOOC.fi Java programming course, but the course materials heavily recommend NetBeans. I already use VSCode for everything else - Python, JavaScript, Markdown. I didn’t want to install another heavy IDE just for one course.

I searched for alternatives. Reddit threads mentioned VSCode works with MOOC.fi, but the instructions were scattered. Some said “just copy-paste to NetBeans when done” which sounded tedious.

The question was: Can I actually use VSCode with full MOOC.fi integration, or would I be stuck with a crippled workflow?

Environment

macOS (same process works on Windows/Linux)
VS Code 1.85+
Java 17 (OpenJDK)
No NetBeans installed

What I Found

MOOC.fi officially supports VSCode through the TMC (Test My Code) extension. This wasn’t obvious from the course landing page, which pushes NetBeans heavily. But after digging, I found official documentation at mooc.fi/en/installation/vscode/.

The TMC extension handles:

Downloading course exercises
Running local tests
Submitting solutions to the TMC server
Tracking progress

This meant I could use VSCode without sacrificing any course functionality.

The Setup Process

Step 1: Install Java Development Kit

First, I needed JDK. I checked if I already had it:

java -version

If you see “java: command not found”, you need to install it.

On macOS:

brew install openjdk@17

On Windows:

choco install openjdk

On Linux (Ubuntu/Debian):

sudo apt install openjdk-17-jdk

Verify installation:

java -version
javac -version

I saw something like:

openjdk version "17.0.9" 2023-10-17
OpenJDK Runtime Environment Homebrew (build 17.0.9+0)
OpenJDK 64-Bit Server VM Homebrew (build 17.0.9+0, mixed mode, sharing)

Step 2: Install Java Extensions in VSCode

I opened VSCode and installed the Extension Pack for Java. This bundle includes:

Language Support for Java (Red Hat)
Debugger for Java
Test Runner for Java
Maven for Java
Project Manager for Java
IntelliCode

Quick install via Command Palette (Cmd+Shift+P / Ctrl+Shift+P):

ext install vscjava.vscode-java-pack

After installation, VSCode took a minute to download and initialize the Java Language Server. I saw a notification saying “Opening Java Projects…” in the status bar.

Step 3: Install TMC Extension

This is the key piece. The TMC (Test My Code) extension connects VSCode to MOOC.fi’s exercise system.

Install via Quick Open (Cmd+P / Ctrl+P):

ext install moocfi.test-my-code

Alternatively, search for “Test My Code” in the Extensions panel (Cmd+Shift+X).

After installation, I saw a new “TMC” icon in the Activity Bar (left sidebar). This is the TMC Commands panel.

Step 4: Configure TMC

I opened the TMC panel and clicked “Login”. The extension prompted for my mooc.fi credentials. If you don’t have an account, create one at mooc.fi (free).

After logging in, I needed to select a course:

Click “Select Course” in the TMC panel
Choose “Java Programming I” or “Java Programming II”
Select your organization (University of Helsinki or other partner)

Then I downloaded exercises:

Click “Download Exercises”
Choose a folder location (I used ~/Projects/mooc-java)
Select which week’s exercises to download (start with Week 1)

Step 5: Understanding the Project Structure

The TMC extension created this structure:

mooc-java/
├── src/
│   └── Part01/
│       └── Part01_01.Sandbox/
│           ├── src/
│           │   └── Main.java
│           └── test/
│               └── MainTest.java
├── lib/
│   └── junit-4.10.jar
└── .tmcproject.yml

Each exercise has:

src/ - Your code goes here
test/ - Hidden tests (you don’t see these before submission)
.tmcproject.yml - TMC configuration

Important: Open the project folder in VSCode (not individual files). The Java Language Server needs the folder context to work properly.

Step 6: Completing an Exercise

I opened Part01_01.Sandbox/src/Main.java:

public class Main {
    public static void main(String[] args) {
        // Write your code here

    }
}

I wrote a simple solution:

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

Step 7: Running Tests

In the TMC panel, I clicked “Run Tests”. The extension ran local tests and showed results in the output panel.

TMC: Running tests for Part01_01.Sandbox...
[INFO] Scanning for projects...
[INFO]
[INFO] ----------------< tmc:Part01_01.Sandbox >----------------
[INFO] Building Part01_01.Sandbox 1.0
[INFO] --------------------------------[ jar ]---------------------------------
[INFO]
[INFO] --- exec-maven-plugin:3.0.0:java (test) @ Part01_01.Sandbox ---
Running tests...
Tests: 1, Failures: 0, Skipped: 0

[PASS] All tests passed!

When tests passed, I clicked “Submit to Server” in the TMC panel. The extension uploaded my solution and I got feedback:

TMC: Submitting to server...
Submission accepted!
Points: 1/1
You can view the submission at: https://tmc.mooc.fi/submissions/...

Common Issues I Hit

Issue 1: Java Language Server Not Starting

After opening the project, I saw errors like “Java Language Server crashed” or no autocomplete.

The problem: VSCode didn’t recognize the project as a Java project because I opened it as a folder, not specifically configured for Java.

Fix:

Make sure you opened the folder (File > Open Folder), not just a file
Check if JDK is in your PATH: java -version
Reload VSCode window: Cmd+Shift+P > “Developer: Reload Window”
If still broken, check the Java extension is enabled

Issue 2: TMC Extension Won’t Connect

The TMC panel showed “Not logged in” repeatedly even after entering credentials.

The problem: Credentials weren’t saved or network was blocked.

Fix:

Logout first: TMC panel > “Logout”
Login again with correct credentials
If using a corporate network, check if firewall blocks tmc.mooc.fi
Clear TMC cache: Cmd+Shift+P > “TMC: Clear Cache”

Issue 3: Tests Fail Locally but Pass on Server

This happened when my solution had timing issues or platform-specific code.

The problem: Local test environment differs slightly from TMC server.

Fix:

Don’t rely on system-specific paths or timing
Make tests deterministic (no random values without seeds)
Check the TMC output for specific error messages

Issue 4: Wrong Java Version

I got errors about Java version incompatibility.

The problem: The course exercises target Java 8+, but I had a different version configured.

Fix in settings.json:

{
  "java.configuration.runtimes": [
    {
      "name": "JavaSE-17",
      "path": "/path/to/jdk-17",
      "default": true
    }
  ]
}

VSCode vs NetBeans for MOOC

After using VSCode for a few weeks, here’s my comparison:

Feature	VSCode	NetBeans
Startup time	~2 seconds	~10 seconds
Memory usage	~400MB	~800MB
TMC integration	Full support	Full support
Learning curve	Medium	Higher
Extensions	30,000+	~1,500
Industry adoption	Very high	Moderate

VSCode advantages:

Lightweight - runs well on older hardware
Same editor for Java, Python, JavaScript
Excellent Git integration built-in
IntelliCode for AI-assisted completions
Larger community = more Stack Overflow answers

NetBeans advantages:

Course materials reference it directly
Zero setup - works out of the box
Better Java-specific refactoring tools
More integrated Maven support

If you’re already comfortable with VSCode, stick with it. The TMC extension provides feature parity for the course.

The Architecture

Here’s how the pieces connect:

┌─────────────────┐
│    VS Code      │
│  (Your Editor)  │
└────────┬────────┘
         │
    ┌────┴────┐
    │         │
    ▼         ▼
┌───────┐  ┌─────────────┐
│ Java  │  │     TMC     │
│ Pack  │  │  Extension  │
└───┬───┘  └──────┬──────┘
    │             │
    ▼             ▼
┌───────┐  ┌─────────────┐
│  JDK  │  │  TMC Server  │
│       │  │ (mooc.fi)    │
└───────┘  └─────────────┘
    │             │
    ▼             ▼
┌───────────────────────┐
│  Your Java Exercise   │
│  (.java files)        │
└───────────────────────┘

The Java extension provides language support (autocomplete, debugging, error checking). The TMC extension handles exercise management (download, test, submit). They work together on your Java files.

Tips I Wish I Knew Earlier

Use Keyboard Shortcuts

I set up shortcuts for common TMC actions:

Cmd+Shift+T R - Run tests
Cmd+Shift+T S - Submit to server
Cmd+Shift+T D - Download exercises

Configure in VSCode’s Keyboard Shortcuts (Cmd+K Cmd+S).

Version Control Your Progress

I initialized Git in my mooc-java folder:

cd ~/Projects/mooc-java
git init
git add .
git commit -m "Initial commit"

After each exercise, I commit:

git add .
git commit -m "Complete Part01_01.Sandbox"

This saved me once when I broke my code and needed to revert.

Debug with Breakpoints

VSCode’s Java debugger works with TMC exercises. I can set breakpoints, step through code, and inspect variables. This helped me understand complex loops.

Click next to a line number to set a breakpoint, then F5 to start debugging.

Keep Extensions Updated

The TMC extension gets updates. Check periodically:

Open Extensions panel
Search for “Test My Code”
Click “Update” if available

Updates fix bugs and add features.

Summary

I set up VSCode to work with MOOC.fi’s Java course using the TMC extension. The full integration means I can download exercises, run tests, and submit solutions without leaving VSCode.

The setup takes about 10 minutes:

Install JDK
Install Extension Pack for Java
Install TMC extension
Login to mooc.fi
Download exercises

I avoided installing NetBeans, kept my familiar VSCode workflow, and maintained full course functionality. If you’re already a VSCode user, there’s no reason to switch IDEs for this course.

Final Words + More Resources

My intention with this article was to help others share my knowledge and experience. If you want to contact me, you can contact by email: Email me

Here are also the most important links from this article along with some further resources that will help you in this scope:

Oh, and if you found these resources useful, don’t forget to support me by starring the repo on GitHub!

How to Use VSCode with MOOC.fi Java Course (Instead of NetBeans)

The Problem

Environment

What I Found

The Setup Process

Step 1: Install Java Development Kit

Step 2: Install Java Extensions in VSCode

Step 3: Install TMC Extension

Step 4: Configure TMC

Step 5: Understanding the Project Structure

Step 6: Completing an Exercise

Step 7: Running Tests

Common Issues I Hit

Issue 1: Java Language Server Not Starting

Issue 2: TMC Extension Won’t Connect

Issue 3: Tests Fail Locally but Pass on Server

Issue 4: Wrong Java Version

VSCode vs NetBeans for MOOC

The Architecture

Tips I Wish I Knew Earlier

Use Keyboard Shortcuts

Version Control Your Progress

Debug with Breakpoints

Keep Extensions Updated

Summary

Final Words + More Resources

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