Understanding of Java Enterprise Edition libraries from 'Javax' to 'Jakarta'

Let me begin by saying that I recommend you start a tech blog. By sharing your knowledge and writing it down, you learn more. It also motivates you to try new things so you can write about them too.

How It All Started: A Curious Encounter with 'Javax' and 'Jakarta'

A few weeks ago, I was handed a backend project at work (let’s keep the project name under wraps—it’s top secret!). The tech stack? Java, of course. My task was to design some APIs, assign functionalities for each API call, and implement the necessary operations. Pretty standard stuff, right? Everything was going smoothly until it came time to deploy the project on the Payara server. That’s when things started to fall apart. Errors popped up left and right. After some debugging, I realized the issue wasn’t in my code (thankfully!) but rather in the compatibility between the Java EE libraries and Payara.

Curious to understand what was going wrong, I went into the versions of the Java EE libraries. That’s when I stumbled upon something interesting: the older javax libraries I was working with had been renamed to jakarta in the newer versions. This raised so many questions—why the rename? What’s the difference? And most importantly, how does this affect developers like me?

In the rest of this article, I’ll share what I uncovered during my research, along with the challenges I faced, the pros and cons of these changes, and why this transition matters in the tech world.

Why the Change from Javax to Jakarta?

So, as I was, scratching my head over deployment errors, when I stumbled upon the shift from javax to jakarta. Naturally, I wondered why the rebranding.

Java EE (Enterprise Edition) was traditionally managed by Oracle under the Java Community Process. In 2017, Oracle decided to donate Java EE to the Eclipse Foundation, aiming to foster a more open and community-driven development model. This initiative was named Eclipse Enterprise for Java (EE4J). While this move was largely welcomed, it came with certain stipulations. Oracle retained the rights to the "Java" trademark and the Javax namespace. Consequently, the community faced a limitation: they couldn't modify or evolve the Javax package namespace under the new governance.

To navigate this, the community rebranded Java EE as Jakarta EE, drawing inspiration from Jakarta, the capital city of Indonesia, located on the island of Java. It signified a new era of open governance and innovation. A pivotal aspect of this transition was shifting the package namespace from javax.* to jakarta.*, officially implemented in Jakarta EE 9.

Why Does This Matter?

The namespace change is more than a simple rename. It empowers the Jakarta EE community to evolve and enhance the APIs without legal constraints, paving the way for modern features and improvements. However, this also means that existing applications using Javax packages need to migrate to the Jakarta namespace to leverage future Jakarta EE advancements.

This shift from Javax to Jakarta is a significant change in the Java ecosystem, influencing how developers like me maintain and upgrade their applications.

What Changed? A Dive into the Transition from Javax to Jakarta

As I navigated the deployment challenges, I realized that the shift from javax to jakarta wasn't just a simple rename.I will share some of the insights which I noticed and learnt in this process of transition:

Namespace transition

Obviously the first and most prominent change is the renaming of the package namespace from javax.* to jakarta.*. This means that all Java EE APIs have been relocated to the new jakarta namespace. For instance, javax.servlet is now jakarta.servlet. Along with this, specification names have been updated to align with the Jakarta EE naming conventions.
API Enhancements and Removals

Even though I didn’t come across when I was working on the project, I thought including this would be great to learn. So Over time, Java EE had accumulated legacy APIs that were marked as "deprecated" - no longer recommended for use because better alternatives existed. These APIs remained in the platform for backward compatibility, but they increased maintenance complexity and other issues. Eliminating these makes Jakarta lighter and easier to maintain and it becomes more stable and efficient.

Certain features dependent on outdated technologies, such as CORBA and XML RPC, have been removed to keep the platform up to date.
Impact on Development and Deployment

The changes had both positive and negative effects on developers around the tech world. Existing applications and servers that were running on Javax should be migrated to Jakarta. Imports and dependencies must be updated to be compatible with the latest Jakarta versions. Third-party libraries and frameworks also need to support the new namespace, necessitating updates or replacements in our projects.

Although adapting and understanding to these changes is crucial for a smooth transition and to leverage the advancements in Jakarta EE, the constructive side of this transition will modernize its ecosystem with the new player ‘Eclipse Foundation' coming in. This decentralization means no single entity dominates decision-making which results in

Gain more support from an active developer community
Improve support for microservices architecture
Transition to Cloud Native Java
Innovate faster and become more agile
Offer high-quality reference implementations for production

My Experience: Navigating the Transition

When I started working on deploying my project, everything seemed straightforward, until I hit my first roadblock - deploying on Payara. For those unfamiliar, Payara is an open-source application server, a successor to GlassFish, and widely used for running Java EE applications. It's reliable, robust, and supports a wide range of enterprise features.

Here’s where the trouble began. Payara has strict version compatibility when it comes to javax and jakarta.

Payara 5 supports javax, but it doesn’t recognize jakarta.
Payara 6, on the other hand, works exclusively with jakarta.

Similarly, Tomcat, another popular Java-based web server, follows the same pattern:

Tomcat 9 uses javax.
Tomcat 10 uses jakarta.

Of course, I didn’t know any of this at the time! When I tried to deploy on Payara, the server gave me errors faster than I could read them. After a lot of frustration and trial-and-error debugging, my senior colleagues helped out. They explained the versioning problem and showed me which libraries and server versions to use together. Thanks to my senior mates 🙌.

As I delved deeper, I also uncovered another compatibility issue that most of the people face: the Java version requirements.

javax libraries require Java 7 or higher, which aligns with the older versions of Java EE.
jakarta, however, requires Java 11 or higher to avoid dependency issues.

Many third-party libraries still use javax, which causes compatibility issues when upgrading to Jakarta EE. This is another important factor I had to consider after learning about these differences.

This experience, while frustrating, taught me the importance of understanding compatibility requirements before starting a project. It also highlighted the need for careful planning when transitioning to newer technologies, especially when legacy systems are involved. Thankfully, with some help and a lot of patience, I managed to overcome these hurdles.

Pros and Cons of the Transition

After diving deep into this transition and facing some challenges myself, I realized that the shift from javax to jakarta isn't just an irritation. In the words of Thanos, it's a double-edged sword with both benefits and drawbacks. Here’s what I think about it:

The Pros: Why the Change is Good

Future-Proofing the Platform
Moving to jakarta ensures the platform can evolve without legal or licensing constraints. This opens up opportunities for innovation, new features, and faster updates.
Improved Java Version Support
By requiring Java 11 or higher, Jakarta EE aligns itself with modern Java features like modules, lambda expressions, and better performance enhancements.
Open-Source Community
Jakarta EE's move to the Eclipse Foundation makes it a project driven by the community, not just by companies. This change promotes teamwork and inclusivity as it grows.

The Cons: Why It’s a Nuisance

Migration
Let’s be honest: refactoring all those javax imports to jakarta in a large project can be a massive headache. Add in dependency issues, and it feels like you're playing a game of Jenga with your codebase.
Tooling and Framework Gaps
Not all tools, libraries, and frameworks have fully caught up with Jakarta EE yet. This means you might encounter unexpected incompatibilities when upgrading.
Steep Learning Curve
For teams unfamiliar with the transition, the learning curve can slow down productivity. From understanding the new namespace to troubleshooting server compatibility, it's not exactly beginner-friendly, I suppose I can say this.

For me, the transition was frustrating at first, but after resolving the issues and seeing the bigger picture, I could appreciate why this change was necessary.

Conclusion: Wrapping It Up

Reflecting on my experience, Initially, it was frustrating - deployments failed, errors multiplied, and I found myself questioning why such a disruptive change was even necessary. But later, I started to appreciate the bigger picture.

Change is rarely easy, especially with technologies that have been around for a long time. Javax was a solid base for many enterprise applications. But technology must evolve to stay current, and moving to Jakarta is a step toward modernization. By adopting open governance, aligning with newer Java versions, and simplifying the ecosystem, Jakarta EE prepares enterprise Java to stay competitive and innovative in the future.

As developers, we often get frustrated with debugging and fixing issues. But when we take a step back, we can see the reasons for these changes. They aren't just obstacles, they're steps that help us create better, more scalable, and future-ready applications.

So, if you're about to start this journey—whether you're dealing with migration problems or server errors—stay patient. With some patience and the right resources, you'll get through it, just like I did. And who knows? You might discover new ideas along the way.