Integrating use cases and functional requirements, where functional requirements are things like: “the system must do xyz” and each such requriement …
Integrating use cases and functional requirements, where functional requirements are things like: “the system must do xyz” and each such requriement is sepatately testable is sometimes a big question in the corporation.
In the words of Alistair Cockburn:
“If you are writing use cases as requirements keep two things in mind:
They really are requirements. You shouldn’t have to convert them into some other form of behavioral requirements. Properly written, they accurately detail what the system should do.
They are not all of the requirements. They don’t detail external interfaces, data formats, business rules, and complex formulae. They constitute only a fraction (perhaps a third) of all the requirements you need to collect-a very important fraction but a fraction nonetheless.”
Thus use cases can represent functional requirements. Other requirements, such as system availability, security, scalability, performance, etc. cannot be represented by use cases.