Java: Three Decades, Three Lessons

Tue, 01 Jul 2025 12:10:00 +0000
Java, uncoverjava, pattern matching, Programming Languages

Thirty years ago, the little Duke appeared in the tech scene, and Java introduced its bold promise to “write once, run anywhere.” Now, in 2025, Java is still the backbone of enterprise software, driving everything from insurtech platforms to the crypto wallets that are fast becoming fixtures inside modern banking apps.

I spend most of my days translating engineering excellence into business value. Yet every great story starts with the voice of the people who live it. I reached out to four of our senior engineers, Sebastian, Emil, Darek, and Jacek, and asked them for the lessons they would pass on to the next generation of Java developers.

Enjoy three decades, three(ish) lessons told by the people who write production code every day. Happy birthday, Java! 🎂

Syntax is just a surface

Learning my first language was like learning magic. I just wrote a few lines of code, and something happened on the monitor. That was incredible.

At the start, everything felt easy and understandable. I learned the syntax, explored the popular features. Got familiar with collections, loops, exceptions, and even found something about multithreading. I thought, “If I just get better at the language, I’ll be able to build anything.”

But, as the ideas grew, I hit the “reality check” wall.

I found out that knowing the language isn’t enough to build real software. Now, I need to know about Spring Boot, databases, Rest API, and "deployment" whatever that meant at the time.

As a software developer, I realized that was just the tip of the iceberg.

To create a good product, I can't just focus on writing code. Now our goal is not just to create something. We want this product to last long. We need to test if business requirements are met and ensure that our changes won't destroy everything. We want to make our app secure, observable, and maintainable.

This made me realize an important truth: writing Java means working with an entire ecosystem. I had to learn about tools, frameworks, and libraries.

I’ve learned much of this from developers whom I met at local meetups like WrocławJug and various conferences. The funny part is that many of those people were not Java developers, yet we could share experience and knowledge. That’s because these are problems we all face, regardless of the language we use.

So if you're on this journey too, remember: the language is just the entry point. The real craft lies in everything that surrounds it.

From Java 6 to 22: Watch how far we've come

Java is no longer slow

Java has carried a reputation for being slow for years. I’ve been hearing that a lot, even when programming was just a hobby.

And sure, on the surface, that made sense. Java runs on a virtual machine, has a garbage collector, and offers layers of abstraction. That felt heavy.

Even in 2011 Robert Hundt wrote a paper “Loop Recognition in C++/Java/Go/Scala“ where he analyzed and...