The first dependency injection framework i learned was Nucleus [1]. An unusual feature of Nucleus is that it has no type-based autowiring. You write a little pr

The first dependency injection framework i learned was Nucleus [1]. An unusual feature of Nucleus is that it has no type-based autowiring. You write a little properties file for every component, and to inject a component into another, the recipient uses the path to the other component's properties file. It is shockingly basic, but it works really well. Everything is explicit, but simple enough that it's not laborious to use. Having multiple instances of components is trivial, because they're just separate properties files. Indeed, the driving use case for Nucleus, the ATG commerce framework (since bought by Oracle) had multiple instances of many classes (eg the generic ORM repository class, for different siloes of data). I was really surprised when i first used an autowiring dependency injection framework, where this is either impossible, or you have to jump through hoops to do it. [1] https://docs.oracle.com/cd/E41069_01/Platform.11-0/ATGPlatformProgGuide/html/s0201nucleusorganizingjavabeancompone01.html https://docs.oracle.com/cd/E41069_01/Platform.11-0/ATGPlatfo...