My first contact with a declarative REST client was with Feign, back then part of the Spring Cloud Netflix stack, long ago relabelled as Spring Cloud OpenFeign. Prior to that, it was always tedious to write those HTTP calls via the RestTemplate, similar code every time. With Feign you just…

Builders in Lombok are amazing. They’re being automatically produced by just adding an annotation above your class and there you go. No need to write tedious boilerplate code. Most of the time, you can use them without further thinking and adaptations. However, sometimes we have special requirements that don’t fit…

Stack traces are undoubtedly a very useful instrument for tracing the processing flow in the event of an error. Error messages, invocation hierarchy, root causes, not necessarily in a very compact format, but it provides valuable information for us developers. Sooner or later, however, you will notice that stack traces…

In today’s blog post, we cover a topic that at first seems pretty trivial to programmers outside of the world of Reactive Programming. I’m talking about “try-catch-finally”. Most programming languages offer keywords for this purpose, so it is very easy to implement and use. In a try block we perform…

When starting with Reactive Programming, some operators are easy to grasp and some are rather difficult to understand. Some operators share a common purpose, like map and flatMap that both transform the input type into some potential different output type. …

Today’s blog post stems from a recent discovery in a customer project. We are maintaining a service that was suffering from a performance problem. The service prepares infrastructural data from various sources and offers them to the outside world, nothing extraordinary. …

Today, at peak times customer facing applications often have to cope with tens of thousands or more simultaneous requests. While cloud computing and the accompanying possibilities of dynamic scaling of applications help to overcome this, they also reach their limits at some point. …

I’m a passionate Scala developer. I like the language and the concepts behind it and especially the stuff you’re able to do that only few general-purpose language support. …

At Digital Frontiers we all have our favourite languages. The other day we were arguing about advantages and shortcomings of some specific ones and decided to have a closer look at them, using a Sudoku verifier as common example. …