Using Java in Fintech: Benefits, Pitfalls, and Hacks

Why is Java so popular now in Fintech?

The history of programming languages teaches us that every year, a new language or even several of them emerge and make hype. Everyone wants to use them. But in a few years, no one remembers its name.

If a company or startup chooses Java, it's 100% guaranteed that they choose popular and up-to-date technology that will retain this reputation in the future. Java was, is, and will be. 

Java is a general-purpose, object-oriented programing language. You can use it for any application, but it is often used for Fintech apps. As for its popularity, there are several reasons for that.

1. Java is a time-tested and robust language. Just like the coffee beans that lent it their name straight from the Indonesian island and kept its founding engineers wide awake. Java’s first version was released in 1995, so it's not a one- or three-year-old language with many bugs, lacking strong features and key functions, etc. During all those years, a strong community of developers has been on the watch for bugs and vulnerabilities, eliminating them timely.
   
2. You’ll get lots of free frameworks, libraries, communities, and foundations. So, you won't need to invent the wheel when developing something: in most cases, you can find a library that suits your purpose and use it for free. The same applies to frameworks for almost any offering: you don’t need to buy the license or pay anything, yet you can build commercial solutions. However, the paid versions of Java products can give you additional benefits, so if your budget is not too tight, explore them as well.
   
3. Java world offers freedom of choice. If you need a specific library or framework to use in your application, there’ll always be a few variants to choose from. Even Java itself is available from a few vendors: you can download Java distributive from Oracle, Amazon, IBM, Red Hat, Eclipse Foundation, etc.
   
4. Java platform has built-in features to ensure security. It verifies code before its execution and ensures that only authorized code can access system resources or network connections. Also, Java doesn't allow applications to access memory not allocated to it and many other security actions.
   If there’s a bug in Java, a hotfix follows immediately. So, if you are using the latest Java version, you can be sure that it’s not Java to blame for a vulnerability in your solution.

5. Scalability features are there, too. If you’re cloud-based, Java will allow you to run multiple server instances automatically without any actions on your side. An important note regarding security and scalability is that, in most cases, companies do not use standalone features and choose specific implementation frameworks. For example, the Spring framework has a security model that allows to organize permissions and access based on tokens, roles, and so on.

6. Java is salvation for startups. The language's affordability and efficiency let emerging companies cut their technology spending without sacrificing quality. You pay for cloud services and/or your own hardware, and your tech team's work, and that's it. This makes Java one of the best options when developing a new offering to impress the market.

Let’s see how Java can improve a Fintech product

I’ll use mail merging as an example. It's a common feature in many applications when you have a document template with some variables, which should be replaced with real data, and you need to generate a Word document, a PDF, etc.

To handle this, we can use various text processors like Microsoft Office, LibreOffice, and Open Office. Each of them provides an API, including Java API, or there are some third-party solutions by using which you can connect or interact with these text processors so we can do a mail merge.

Here’s how it works. We take, say, a Microsoft Word template, tell the text processor to replace those variables with data, and then generate a PDF, Microsoft Excel, or CSV file. So, we use production robust external applications with minimal effort and considerable value for the users. Now, they’ll be able to quickly generate reports or letters, customize them, and send them via email, which Java can enable. 

Does Java have any drawbacks?

Java is perfect. 
Just kidding. 
It certainly has some room for improvement but nothing drastic. Since Java is an established language with decades of history, some decisions taken long ago may slow down development. Indeed, some languages, object-oriented or not, allow building some proofs of concept (POCs) from scratch more quickly. 
From my experience, however, when a startup grows, it tends to rewrite that POC using more strong, enterprise solutions—like Java and Java-related technologies. So, if you may end up with Java anyway, it certainly makes sense to consider this language initially.