Slide 6 of 42
Notes:
(Here weíve imporved the example type model a little.)
Snapshots are used to illustrate, animate, and help visualise goals and formal constraints.
A snapshot is an instance diagram that shows examples of the states immediately before and after a typical occurrence of a use-case. (The ëafterí state is usually shown in red or in bolder lines.)
A snapshot must conform to the type diagram associated with the use case it is illustrating. Purchasers and Vendors in this example are varieties of Owner; every Owner has a set of possessions, each of which is a Thing: so the snapshot shows some owners e
(In a tools that doesnít support drawing lines and boxes in different colors, attach annotations ìnewî and ìdeletedî.)
When a snapshot is used to illustrate a goal, it doesnít include messages between the objects: these are added in a later phase of design.
