BTS 330 Understanding User Requirements 1 Requirements n

BTS 330 Understanding User Requirements 1

Requirements n Steps: n n n Define vision/scope Identify users/stakeholders Identify use cases n n Understand what interaction is happening with the system Identify business rules 2

Use Case Modeling n Actor n n Represent anything outside the system that uses the system to do something From your stakeholder list, identify those ‘stakeholders’ that will actually use the system those are the actors

Use Case Modeling n Actor n Give them a name – use a name that describes the role that the actor plays in relation to the system n n n i. e. Fitness Instructor, member, manager Really a role that a person (or system, or device) plays when using the system Give the actor a brief description

Use Case Modeling n Fitness Instructor n n Member n n Instructs fitness classes Uses the club’s facilities and services manager n Is responsible for overseeing the operation of the club and managing the employees

Use Case Modeling n Actor Tip: n n Every system requires an actor to start the system and to shut it down the actor is anything outside the system that exchanges information with the system Every system requires some sort of maintenance to be done n i. e. backup – actor is ‘system clock’

Use Case Modeling n Actor n A person, software system, department, role, device…etc…. outside of the system that interacts with the system Actor System Actor

Use Case Modeling n Use cases: n n Express the behaviour of the system that produce a measurable result of value to an actor Describe things actors want the system to do n n n i. e. query the status of an order How do the users use the system? Each major system ‘usage’ is a use case n i. e. Process A Membership, Manage Fitness Classes, Maintain Employee 8

Use Case Modeling n Use case: n n A sequence of interactions between a system and an external actor Accomplishes a ‘useful’ goal; something of value to the user 9

Use Case Modeling n Actors communicate with the system to: n n n Start a use case Ask for some data stored in the system which the use case presents to the actor Change data stored in the system by means of a dialog with the system (request some data, change it and save it) 10

Use Case Modeling n Use cases communicate with the actor to: n n n Report that something special has happened in the system that the actor should be aware of Ask an actor for help in making a decision needed to achieve a goal Delegate responsibility to an actor 11

Use Case Modeling n Identifying use cases n n n For each actor list the interaction they must have with the system The interaction should be a ‘goal’ that the actor wants to accomplish by using the system Name the interaction use a verb to name the interaction n i. e. Schedule A Class, Process A Membership

Use Case Modeling n n Use cases are usually completed in a short period of time If parts of the use case are widely separated in time and performed by different actors, then those parts are probably better as separate use cases

Use Case Modeling n Identifying use cases tips: n n What functions will the actor want from the system? Does the system store information? What actors will create, read, update, or delete that information? Does the system need to notify an actor about changes in its internal state? Are there any external events that the system must know about? What actor informs the system about those events?

Use Case Modeling n Identifying use cases n n Every system starts from a vision Vision can tell us the key features required of the system, possible constraints and who the stakeholders might be

In-class Exercise n Jim’s Gym n For Jim’s Gym who needs to acquire an automated computer system to run his new business, the Gym Management System is an information system that will provide a single point of access to manage his gym. The system will provide the capability to manage all aspects of Jim’s business such as managing members and fitness staff, schedule employees and fitness classes as well as a gift shop. There will also be services such as massage therapy and private and semi-private instruction with a fitness instructor offered. Unlike the competition, our product will allow members to manage their experience at Jim’s gym through an interactive web interface where customers can sign up for classes and services that the gym will be offering.

In-Class Exercise n From the vision statement: n Stakeholders: n n n Jim Fitness instructors Use Cases: n n n n Manage Members Manage Staff Schedule Employees Schedule Classes Gift Shop Massage Therapy Private, semi-private instruction Sign up for classes

In-Class Exercise n n Which of these will an actor need to interact with the system? Which of these will require further analysis to determine who the actors need to be and what interaction they need to have with the system? n n n n Manage Members Manage Staff Schedule Employees Schedule Classes Gift Shop Massage Therapy Private, semi-private instruction Sign up for classes

In-Class Exercise n For your business, start with your vision statement n n Identify who the stakeholders are Identify the use cases by listing the interaction the actor needs to have with the system (you might be able to identify some of the interaction from your vision statement)