Software Testing and Quality
Assurance
Lecture 18 - Test Analysis &
Design Models (Chapter 4, A Practical Guide
to Testing Object-Oriented Software)
1
Lecture Outline

Testing Specific Types of Models


Requirements model
Analysis models

Domain analysis model



Architectural design model
Detailed class design model
Application analysis model
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Testing specific types of models:
requirements model


Acceptance testing often finds faults that result
from problems with the requirements
 (missing requirements, contradiction in
requirements).
There is no UML model on which the
requirements are based,
 So, comparison to the basis model refer to
documents produced by marketing, system
engineering or client organization.
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Testing specific types of models:
requirements model (cont...)

Outline of testing the requirements
models:


Develop the ranking of use cases by
computing combined frequency and
criticality information for a use case.
Determine the total number of test cases
that can be constructed given the amount
of resources available.
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Testing specific types of models:
requirements model (cont...)



Ration the tests based on the ranking
Write scenarios based only on the
knowledge of those in the domain
expert’s role
Check for completeness, consistency,
and correctness
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Testing specific types of models:
requirements model example (cont...)
Use
Start Brickles
Frequency
Criticality
Combined
value
Rank
Number of
test cases
Medium
High
High
1
3
Low
Low
Low
3
1
Medium
Low
Medium
2
2
High
High
High
1
3
Wins
Medium
High
High
1
3
Loses
Medium
Low
Medium
2
2
Pause
Brickles
Stop Brickles
Break brick
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Testing specific types of models:
requirements model (cont...)

Criteria for requirement inspection:
Criteria
Interpretation for domain modeling
Completeness
The use cases represent all of the functionality
needed for a satisfactory product. No use case
is needed that is not required functionality.
Correctness
Each use case accurately represents a
requirement.
Consistency
Any system functionality is specified in the
same manner everywhere it is described.
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Testing specific types of models:
analysis models



Domain analysis model
Application analysis model
A domain model is a representation of
the knowledge in a domain as seen
through the eyes of a set of domain
experts.
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Testing specific types of models:
analysis models— domain analysis
model

Two groups are formed:


Group one: developers group ―creates
the domain model
Group two: testers and domain expert
group ―serves as testers of that model.
(this group creates the test cases of the
model).
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Testing specific types of models:
analysis models— domain analysis
model (cont...)

Criteria for domain analysis model
inspection
Criteria
Interpretation for domain modeling
Completeness
The concepts are sufficient to cover the scope of the
content specified. Sufficient detail is given to
describe concepts to the required path.
The description of domain concepts are accurate;
the algorithms will produce the expected results
Correctness
Consistency
Model elements should be consistent with
company’s definitions and meanings
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Testing specific types of models:
analysis models— application
analysis model


Multiple domain models contribute to
the single application analysis model.
Criteria for application analysis model
inspection.
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Testing specific types of models:
analysis models— application
analysis model
Criteria
Interpretation for domain modeling
Completeness The ideas expressed in each use case can be
represented by the concepts and algorithms in the
model. No design information is included in the model.
Correctness
Experts agree with the attributes and behaviors assigned
to each concept; on the steps in each algorithm; major
states for each conceptual entity.
Consistency
Where there are multiple ways to represent a concept of
action, those ways are equivalent
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Testing specific types of models:
design models


Architectural design model: provided the
basic structure of the application by
defining how a set of interfaces are
related.
Detailed class design model: provides
the precise semantics of each class and
identifies the architectural interface to
which the class corresponds.
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Testing specific types of models:
design models— architectural
model



The architectural model is the skeleton
of the entire application.
Non-functional requirements are
blended with functional requirements.
A software architectural model is the
basic structure that defines the system
in terms of computational components
and interactions among those
components.
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Testing specific types of models:
design models— architectural
model (cont...)

Representations of the architecture:

To represent an architecture:




Relationships
States
Algorithms
Tool support: Rational Rose performs a variety of
consistency checks on the static-relationship
model.
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Testing specific types of models:
design models— architectural
model (cont...)

Consistency checks will prevent certain types
of connection from being established.


However, it is not sufficient for determining
whether the functionality is correctly implemented
Architecture description languages provide
the capability to represent a system at a high
level of abstraction (e.g. Rapide)
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Testing specific types of models:
design models— architectural
model (cont...)

Testing the architecture:

The Software Architecture Testing (SAT)
technique is a special type of guided
inspection that requires the following steps:



Test cases are constructed.
The tests are conducted on the product
The results of the test are evaluated for
correctness.
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Testing specific types of models:
design models— architectural
model (cont...)

Constructing test cases:


Test cases are constructed from the use
cases.
The test cases for the architecture are
defined at a higher level than more detailed
design models.
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Testing specific types of models:
design models— architectural
model (cont...)
Criteria for the architectural design
Criteria
for the architectural design model
modelInterpretation
inspection:

Completeness
A sufficient set of interfaces are defined to provide all of the
services needed for the application’s functionality. The
relationship between the interfaces allows for the flow of
control and data necessary to realize all of the uses described
in the use case diagram.
Correctness
The architecture satisfies its constraints; uses the
appropriate architecture patterns; represents the
interactions between interfaces.
Each use of the system can be handled only in one set
of interfaces.
Consistency
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Testing specific types of models:
design models— architectural
model (cont...)

Test execution:


Test cases are executed by constructing a
message-sequence diagram.
The diagram reflects preconditions for a
test case.
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Testing specific types of models:
design models— architectural
model (cont...)

Verification of results:


When the output from the test is in the form
of diagrams, the resulting diagrams must
be verified after each test execution by
domain experts.
When the output is the result of an
execution, the test result can be verified by
having those domain experts construct
event sequences that would be produced
by an architecture that performs correctly.
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Key points

Testing the requirements models:





Develop the ranking of use cases by computing
combined frequency and criticality information for
a use case.
Determine the total number of test cases that can
be constructed given the amount of resources
available.
Ration the tests based on the ranking
Write scenarios based only on the knowledge of
those in the domain expert’s role
Check for completeness, consistency, and
correctness
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Key points



A domain model is a representation of the
knowledge in a domain as seen through the
eyes of a set of domain experts.
Multiple domain models contribute to the
single application analysis model.
Design models


Architectural design model
Detailed class design model
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