Just a few days ago I was reviewing a pull request of one of my colleagues. He added a new class with multiple fields, but all they weren’t final. And I wrote a comment “make it final, please”. And that’s why I decided to write this post. Make

In this blog post, I want to explain why interfaces so important when you want to make your application well-structured, maintainable and testable. But before, let me refresh some terms. What is a module?A module is a part of a program. That’s it. Though, every programming language defines