There is a lot of magic in Java. Try Spring Boot for example, and things magically connect together with annotations, or somehow methods get injected onto interface on the fly, or an http interface maps onto a function with parameters because the runtime is doing it. This is most evident when you set a break point in some class and there might be 4 or 5 mystery functions it passed through between it and where you thought it was calling from. Sl4j, Lombok, Hibernate are doing the same kind of thing.