Use case is a Unified Modeling Language (UML) technique to
capture the requirements in form of a figure. A use case diagram displays
relationships between Actors and a Use case. An actor represents a user or
another system that will interact with the system. A Use case is the system
that we are currently showing. Let us see some Use case diagrams before we
actually go through the UML documents.
Figure 2 shows a use case which explains all the operations
of a customer from getting a catalogue for ordering and finally getting the
confirmation of the same.
Use case document is the supporting document for the use
case diagram. It has the description of the use case diagram. It has the following
Brief Description – 2 to 3 sentences about the use case
Pre-conditions – conditions before the use case actually started
Basic flow – the basic control flow
Alternative flow – the alternative control flow
Post conditions – the condition after the use case executes