I Asked ChatGPT to Review My Java Code for 30 Days — Here’s What Happened

If someone had told me a year ago that an AI could review my Java code better than many human developers, I would’ve laughed. But curiosity is dangerous — especially for developers — so I decided to run a 30-day experiment:

Every single day, ChatGPT would review my Java code. No shortcuts. No filters. Just real-world coding.

The results?
Let’s just say my Java skills went through a transformation I didn’t expect. Cleaner architecture. Fewer bugs. Better performance. And, most surprisingly — a completely different way of thinking about code quality.

This is the story of what actually happened.

Week 1 — ChatGPT Made Me Realize How Much Boilerplate I Was Writing

I started with an innocent goal:

“Can you review this code and refactor it using Java 21 best practices?”

What ChatGPT returned blew my mind.

Before

public class OrderService {
    public double calculateTotal(List<Double> prices) {
        double total = 0;
        for (Double price : prices) {
            total += price;
        }
        return total;
    }
}

After

public class OrderService {
    public double calculateTotal(List<Double> prices) {
        // More concise and efficient using Streams…