ABAP RAP Deep Dive — Part 2: Implementing Business Logic, Validations, and Determinations in SAP S/4HANA

If you’ve already laid the groundwork with the ABAP RESTful Application Programming Model, you know that RAP isn’t just another framework — it’s a fundamental shift in how we build business applications on SAP S/4HANA. In Part 1 of this RAP series , we covered the architectural foundations: behavior definitions, business objects, and the basic anatomy of a RAP application. Now it’s time to get our hands dirty. This article focuses on the parts of RAP that truly determine whether your application