5 things to consider when choosing a Java application server

Middleware has the same role yeast has on your dough – it can help you bake the most delicious bakery items or leave a bad taste in your mouth.

30 years after its initial debut, Java still remains one of the most popular programming platforms out there. To give you some context, according to Azul’s 2025 State of Java Survey & Report, 99% of applications in enterprises are built with Java or run on a JVM. Also, in 68% of companies, more than 50% of applications are Java-based.

This portion represents a staggering volume of Java software, considering that the typical enterprise has approximately 1,000 applications and the number soars by 26-28% every year, according to Salesforce’s State of IT Report. With so many Java applications being used for key business operations, choosing the right application server is paramount and can play a key role in driving the success of your team and company.

Ultimately, I like to think that identifying the right technology for your Java applications is a bit like choosing the right yeast for your dough. In effect, middleware, the layer between your application and the operating system, plays the same vital role in software as yeast does in baking.

It can help your applications rise beautifully, develop complexity, and scale under pressure, giving you a golden, resilient system that smells of success (figuratively speaking, of course). However, pick the wrong one and your dough will collapse and ruin your meal. And sure, you can make your sourdough starter from scratch, but who realistically has the time to manage it for a long time?

So, how can you select the right yeast, erhm, application server for your project?

Start with your Java stack and specifications

The process of selecting a Java application server begins with a thorough assessment of the frameworks, technologies, and specifications your applications rely on. More precisely, before evaluating the middleware technology landscape, you need to clearly identify the Java frameworks, such as Jakarta EE, Spring, Quarkus, and APIs your software use, including which versions are used.

Once these details are mapped, they should be used to help you identify a list of potential application servers providing robust support for such specs. By aligning your middleware search with these requirements, you can maximize compatibility and application stability, ensure access to necessary features and APIs without workarounds, while simplifying troubleshooting and maintenance.

For example, applications built with Java EE 8 features will likely not run reliably on a server that supports only more recent Jakarta EE 10 (and above). Moving to such a runtime can lead to potential runtime errors, missing functionality as well as the need to invest in substantial refactoring even, if you were aiming for a simple lift-and-shift.

Define the use case: Development or production?

Another important consideration when looking for an application server is the type of Java applications that it should support. Specifically, will the middleware only support development activities or personal projects? If this is the case, unsupported, open source freeware and community solutions, such as Payara Platform Community, GlassFish, or Tomcat, are likely best suited to address your needs.

However, if the application server needs to handle mission-critical and/or used in production environments, these options are not recommended. In effect, they can fall short in terms of technical support, software updates, security patches, and regulatory compliance. In such cases, enterprise-grade solutions should be considered for their dedicated engineering support, predictable update cycles, and vulnerability management, as well as adherence to industry standards and regulations, such as the European’s Cyber Resilience Act (CRA).

Read more: The crucial role of openness in modern software development

Match the server to your infrastructure

When considering the best middleware alternatives for your Java applications, you should also evaluate the architecture of your application as well as where you want to run it. Namely, it is essential to ask: Is your software a monolith or does it leverage microservices? Should it be deployed on premise or in the cloud?

The answers to these questions can help you further refine the requirements the ideal middleware should meet. For example, if you plan to support a large, monolithic architecture on premise, the lightweight, container-friendly Payara Micro Enterprise would not be recommended, while the full-featured Payara Server Enterprise would be suitable.

Evaluate the feature set

By this point, the list of suitable application server technologies has been narrowed down considerably, but you likely still have a few different options to choose from. To identify the top match, you should define what additional features are a must for your application and your operations, as key functionalities can significantly affect development speed, system performance, and security posture.

You should list everything that you and your development team may need, from key developer productivity tools and integrated development environments (IDEs), to connectors and monitoring platforms, as well as key security features. In addition, make sure the middleware doesn’t just support your application’s current needs, but can scale and evolve alongside it.

Consider cost, licensing, and total ownership

Finally, if you can’t decide between two options, evaluate the available budget, as cost plays a decisive role. When you do so, don’t just compare license fees, look at the total cost of ownership (TCO). Sometimes, a higher upfront investment in a commercial offering can lead to lower maintenance costs and less downtime in the long run, but it’s not always the case.

Key questions you may want to ask include what does the licensing model look like? Is there any vendor lock-in? Are there additional costs for support or JDKs? What is the level of technical assistance provided and how responsive is it?

Ready to bake?

Middleware, like yeast, sits quietly in the background, but its impact is profound. Just as choosing the right yeast is essential to baking bread that rises, holds its shape, and delivers flavor, selecting the right Java application server is fundamental to building stable, scalable, and successful applications. While there are multiple options available, only a few may be able to truly help your applications reach their full potential.

Throughout this piece, we’ve explored the five key elements that can help you make that choice wisely. From understanding your application’s frameworks and specifications, to clarifying whether you’re baking for experimentation or a production-ready feast, aligning the server to your architecture and deployment model, and evaluating the essential features and cost of your middleware options.

It doesn’t take much: Just five simple points but they make all the difference. Now, with the recipe here, the only question left is: Are you ready to bake?

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