Case studies and examples
As with other chapters in this book, let's end this chapter with some practical considerations about how to apply the concepts we've looked at to our recurrent example involving a mobile payment solution. Let's start with encapsulation.
Encapsulating with a hexagonal architecture
A common way to map hexagonal concepts in Java is to encompass the following concept representations:
- The core maps into the domain model. So, here you have the usual entities (Payment, in our example), services (PaymentService, in this case), value objects, and so on. Basically, all the elements in the core are Plain Old Java Objects (POJOs) and some business logic implementations.
- Here, the ports are the interfaces. They are somewhere in the middle, between a logical concept in the domain realm (enquire, notify, and store, in our example) and the respective technical concepts. This will promote the decoupling of the business logic (in the core) and...
