1 project management office lunch & learn use case
Post on 19-Dec-2015
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TRANSCRIPT
1
Project Management Office
Lunch & Learn
Use Case
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Agenda• Definition
• Benefits
• UCIT Methodology & Use Case
• Steps to develop use cases
• Use Case Body Parts
• References
• Questions
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What is a use case?
• Describe goal-oriented set of
interactions between the actor and the
software
• A technique used to identify, detail, and
clarify software requirements
• Focus on WHAT, not HOW
• Define the scope/boundary of the
software
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Use Case Diagram – Membership Sales
Membership Sales (MS)
Client Service Rep
Sell a Membership
Sell a MembershipAdd-On
Add a Locker Rental
Add a Towel Service
«extends»
«extends»
Renew a Membership
Update a Membership
Client
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Benefits• Put requirements in business context• Easy to understand by business & IT community• Validate scope and requirements• Serve as a basis as scheduling and estimating • Manage complexity
− Break software into manageable parts
• Re-useable deliverable− Test Cases− User Manual− Future enhancements
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Steps to develop use case1.Identify actor
2.Identify use case goals for each
actor
3.Identify re-use opportunity
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Example – Membership Sales
Membership Sales (MS)
Client Service Rep
Sell a Membership
Sell a MembershipAdd-On
Add a Locker Rental
Add a Towel Service
«extends»
«extends»
Renew a Membership
Update a Membership
Client
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Steps to develop use case4. Create Use Case Index
5. Validate against requirements
6. Determine execution approach
7. Develop high level use case
8. Create detail use case
9. Walkthrough & Revise
10.Package into final document
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Body Parts - Summary
• Use Case Identifier − Unique identifier assigned to use case− Example MS-001, MS-001.1
• Goal/Name− Describe the BUSINESS goal that the use case is intended to
achieve− Use active verb to describe the performing action on the goal− Example: Register in an event, Issue an ID Card, Renew a
Membership
• Actor− Someone or something outside the system that acts on the
system− Primary or secondary actors− Person/Role, System, or Time
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Body Parts - Scope
• Pre & Post Conditions− Pre Conditions – set of criteria must be satisfied before the
use can be initiated− Post Conditions – describes the states of the software when
the use case ends
• Triggers− Event that causes the use case to be initiated− External, Internal, or Temporal
• Temporal - Send Payroll Deduction to PeopleSoft• Internal – Apply Client Restriction Automatically• Business vs. System Use case
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Body Parts - Scenario
• Main Scenario− Consists of steps required to achieve the business goals− Happy Day Scenario – most likely case
• Alternate Paths− Other possible scenarios − Branch from main scenario when the situation differs
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Body Parts - Exceptions
• Steps taken to deal with failure
• System or human cause−Access to ID Core Service failed−Payment failed to go through Moneris
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More Information
• Books−Writing Effective Use Cases−Patterns for Use Cases
• Websites−www.usecases.org−en.wikipedia.org/use_case
