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Java Bean Validation is an Anti-Pattern

20. März 2022

Letzte Beiträge

Clean Code 20. November 2022

Don't confuse configuration and constants

From time to time I experience that an application is unnecessarily configurable. In a recent project I experienced how too many options lead me to feel much more complexity and increased my mental load. Looking deeper into some of the values I saw that these were actually constants that would be dangerous to change “on-the-fly” anyway. In this post I reflect on this and share my thoughts. In this project the backend processes data from an embedded devices that communicate through LPWA networks.

Marcus Held

Clean Code 20. März 2022

Java Bean Validation is an Anti-Pattern

The javax.validation package is widely used in our industry. And I don’t like it. I believe using bean validation is an anti-pattern. It hides business relevant constraints, it leaves the choice when a validation happens to other framework code, and I even saw cases where developers expected that the validation “just had to take place”, but it never happened. Of course, there was also no test for it. And speaking about tests - testing these business relevant constraints is painful as well.

Marcus Held

Clean Code 6. März 2021

Rules for Extension Functions

In recent reviews I stumbled upon extension functions which didn’t quite felt right, but I wasn’t able to determine where that gut feeling was coming from. After seeing quite a lot of them I came to some conclusions why that’s the case, and I gathered rules for me when extension functions make sense to use and when they should be avoided. I discovered an overuse of the language feature - something you often experience when you work with a new fancy language with nice features.

Marcus Held

Clean Code 23. Januar 2021

Don't Use The Builder Pattern in Kotlin

This week I was taught again that you should be thoughtful when applying patterns you read on the internet (which is ironic - because the same applies to this post ;-) ). This time colleagues heavily applied the Creational Design Patterns in Kotlin: Builder from Baeldung. Using the builder pattern in Kotlin in this example is an anti-pattern and in this post I will reason why you’ll end up with safer, less error-prone and less boilerplate when properly applying Kotlins language features instead of this builder pattern.

Marcus Held

Clean Code 1. November 2020

Favor Polymorphism Over Enumerations

Last week I reviewed the data design of a colleague. He had to improve a feature and while working on it he noticed that the existing design was not sufficient to properly reflect the changes he had to do. Intuitive he followed the practices of other models in the code and introduced an enumeration to distinguish between different alert types that can be created in the application. Using an enumeration for it is not the optimal solution and in this post I want to describe why you should always question when you see an enumeration in your code and think about solving it with polymorphism instead.

Marcus Held