Executable UML: A Foundation for Model-Driven Architecture

2.1. The System Model

We build an executable UML model for each subject matter, or domain, in the system. To establish the domains, we gather requirements expressed as use cases and sort them, based on their vocabularies, into the various subject matters in the system.

Requirement-gathering and domain identification go together. Sometimes we know what the domains are and build use cases against them, and sometimes we have use cases but have to work out what the domains are. Typically, of course, it's a mixture of the two, so we iterate between the two activities.

2.1.1. Domain Identification

Each domain is an autonomous world inhabited by conceptual entities. The conceptual entities in one domain require the existence of other conceptual entities ...