Requirements Engineering
for Web Applications
SR: System Vision Document
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Written by key stakeholders
An executive summary of the solution
A high-level description of the problem that the system
will address as a set of issues stated in business terms.
The list of stakeholders and users of the system with
their descriptions, concerns, and responsibilities.
A list of features of the system expressed in business
terms.
A list of system constraints described in business terms.
A list of nonfunctional constraints related to overall
enterprise environment, including development
standards and processes of the organization, limitation in
cost or resources, etc.
SR: User-Stories
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An effective intermediate step to the use cases
A half-day workshop with representative of the
user community
Ask them to write up what they expect the
possible interactions of the various users with the
system are as stories
Not give the users too much time to write stories.
User stories are a throwaway artifact, not
maintained.
Used as a basis for system use cases
Good for user experience model
User story example
SR: Use Case Model - 1
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Actors
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System use case
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A role played by a person or system that is external to
the system but interacts with it.
A sequence of actions that describe the interaction
between the actors and the system for a specific task
or function
Use case model
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UML diagrams and the use case definitions
A synthetic view of the functionality of the system
Use case template
SR: Use Case Model - 2
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Objectives of the use case model
Produce diagrams that represent the actors
and their relationships (actor diagrams)
 Produce diagrams that represent the use
cases with the actors and their relationships
(use case diagrams)
 Organize the use cases into packages that
map to the conceptual categorization of the
system functions
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Initial UML diagram of actors
Actor Model
Actor Model
SR: Use Case Model - 3
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Use the following to produce first draft of
use cases
User stories
 Business use case model
 Business object model
 Vision document
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Organize use cases into “business
packages”, each of which contributes to
the realization of a specific business
function
Use case model: Acct Mngmnt
Use case Model: Store Front
Use case model: Maintenance
Use case model: Organization
Use case model: mind map
Browse Catalog
Review shopping
cart
Create Account
Store
front
Use
Cases
User Acct
Mngt
Manage Account
Sign in
Checkout
Maintenance
Manage Users
Sign out
Use case model: system
boundary
Browse Catalog
Create Account
Anonymous User
Review shopping
cart
Sign in
Manage Account
Checkout
Registered Buyer
Sign out
Manage Users
Admin
Credit Card System
Use case: sequence diagram
SR: Use Case Model - 4
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Refine use cases
Use a template for use case definition
 Remove any ambiguity
 Resolve conflicts
 Use the business rules to identify alternative
paths in the use cases
 Add concepts that are pertaining to the
system, but the business to the
business/system glossary
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SR: Test cases
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As soon as the use cases are defined, test
designer should start identifying
Test scenarios
 Test cases
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Preparing of test cases can also help in
validating use cases
SR: Summary
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Artifacts of SR
Vision document
 User stories
 Use case definition
 Use case model
 System glossary
 Use case packages
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