Use Case Benefits, and Best Practices

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Use CaseBenefits, and Best Practices
By Harry Penumatsa
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UML Definition The Specification of a set of
actions performed by a system, which yields an
observable result, that is typically of value to
one or more stakeholders of the system
Use Case
In simpler terms, Use case is a Prose
description of a systems behavior when
interacting with the outside world
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Where does a Use Case Apply?
Stakeholder Needs (Business Objectives)
Features
Use Case (Functional)
Supplementary (Non-Functional)
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Structure of Use Case

• Use Case Name
• Description
• Pre Conditions
• Post Conditions
• Flow Of Events
• Basic Flow
• Alternate Flow
• Extension Points
• Special Requirements

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Benefits of Use Case

• Capture and Communicate the desired behavior
  for the system
• Provide a rich context for the functional
  Requirements
• Easily understand and facilitate agreement with
  the stakeholders
• Provide system boundary that prevents scope
  creep by identifying
• who or what interacts with the system
• Avoid Pre Mature Design
• Lead to Test Cases (coverage and Verification)
• A powerful Planning instrument for iterative
  development

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Limitations of Use cases

• Use case flows are not well suited to easily
  capturing non-interaction based requirements of a
  system (non-functional)
• As there are no fully standard definitions of use
  cases, each group must gradually evolve its own
  interpretation.
• Use cases templates do not automatically ensure
  clarity. Clarity depends on the skill of the
  author.
• Use cases can be over-emphasized and can be
  mistaken for a design document
• Sometimes mistaken for a design document when it
  is actually a Requirement document

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How to use use case

• Formulate a strong Requirement Management Plan
• Clearly define the use case as a intermediately
  artifact between Business requirements and system
  requirements
• Communicate the communication plan to all
  stakeholders
• Devise a Use Case Style Guide
• Constantly keep updating use case style guide
  based on the project and the lessons learnt
  during the life cycle

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Use Case Style Guide

• UCSG is a repository of collective wisdom on what
  best suits
• your organization and it should include examples
  and template
• for Use case description.

• Checklist
• Provide Value to Stakeholder
• Complete Narrative describing the Value
• Stand Alone
• Not Design Specific

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Use Case Vs FRD
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Conclusion

• Use Cases provide best value based on the project
  and the process followed to tailor a Use Case
  format to best suit your organization

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Qs n As