Monday

Today will serve a unusual lengthy lecture an introduction to the subject area of Systems Design/Systemudvikling

Agenda:

• Who/what of Applying UML and Patterns

• The concept and motivation for Object Oriented Design and Analysis (OOAD)

• Object Orientation as a way of thinking, designing & engineering

• Introduction to Use Cases

Use cases:

Use cases are written from the perspective of actors and defined in a scenario.

An actor is something with behaviour, such as a person/user, computer system or organization.

A Scenario is a specific sequence of actions and interactions between actors and the system (also known as a use case instance). It is one particular story of using a system - one path through the use case.

• For example searching Momondo for a flight to a particular destination and ending up booking and ordering the ticket(s)

Use cases are considered functional requirements as they dictate how a system should function

• What feature it should have, to live up to the requirements

Use cases exists in three formats:

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Exercise 1: In your study groups

Consider a store such as ProShop, Zalando or Amazon - choose a case.

• Consider - what makes this shop unique?

  • Is it customer to customer sale?

  • Are the items second-hand?

• Describe two brief use cases from the perspective of a potential customer

• Refine one of them to a casual use case

• Refine That one to a fully single use case

Exercise 2

• Create a use case diagram for a user

Exercise 3 (Advanced)

• Describe two brief use cases from the perspective of a administrator

• Refine one of them to a casual use case

• Refine That one to a fully single use case

Exercise 4 (Advanced)

• Create a use case diagram for an administrator/seller