The Ultimate and Complete ICT2622 – Object-Oriented
Analysis Study Guide 2025, Covering Object-Oriented
Systems Analysis Principles, UML Modelling Techniques
and Diagrams, Use Case and Class Diagram
Development, Object Identification and System Modelling,
Requirements Gathering and System Specification
Analysis, Software Development Life Cycle Integration,
Database and System Design Foundations, Encapsulation
Inheritance and Polymorphism Concepts, Real-World
Business System Modelling, Risk and Requirements
Validation Techniques, Practice Questions with Verified
Answers and Detailed Explanations, Step-by-Step UML
Diagram Construction Methods, Case Studies in System
Analysis, and Proven Strategies to Successfully Master
ICT2622 Object-Oriented Analysis
Question 1: In the context of Object-Oriented Analysis and Design, which of the following
best describes the primary purpose of encapsulation when designing a software system's
class architecture?
A. It allows a subclass to inherit all the public and private attributes of its parent class without
any restrictions. B. It bundles the data and the methods that operate on that data within a
single unit, while restricting direct access to some of the object's components. C. It enables a
single interface to represent different underlying forms of data, allowing methods to be used
interchangeably across diverse object types. D. It ensures that a class has only one reason to
change, thereby promoting high cohesion and low coupling across the entire system
architecture.
CORRECT ANSWER: B. It bundles the data and the methods that operate on that data within a
single unit, while restricting direct access to some of the object's components.
Rationale: Encapsulation is a fundamental object-oriented principle that involves bundling the
state (attributes) and behavior (methods) of an object into a single unit (a class) and restricting
direct access to some of the object's components. This is typically achieved through access
modifiers (like private or protected), which protect the internal state of the object from
unintended interference and misuse, thereby enhancing maintainability, security, and
modularity.
,Question 2: When modeling a software system using UML, which relationship between two
classes indicates that one class is a specialized version of another, inheriting its attributes and
operations?
A. Dependency B. Aggregation C. Generalization D. Realization
CORRECT ANSWER: C. Generalization
Rationale: Generalization is the UML relationship that represents inheritance, where a
specialized class (subclass or child) inherits the attributes and operations of a more generalized
class (superclass or parent). This relationship is depicted by a solid line with a hollow, closed
arrowhead pointing from the subclass to the superclass, signifying an "is-a" relationship.
Question 3: In Object-Oriented Analysis, polymorphism is best utilized in a system design to
achieve which of the following primary objectives?
A. To hide the internal implementation details of a class from other classes in the system. B. To
allow objects of different classes to be treated as objects of a common superclass, enabling
interchangeable behavior. C. To ensure that a class is instantiated only once throughout the
entire lifecycle of the application. D. To combine multiple interfaces into a single, simplified
interface for a complex subsystem.
CORRECT ANSWER: B. To allow objects of different classes to be treated as objects of a
common superclass, enabling interchangeable behavior.
Rationale: Polymorphism allows methods to do different things based on the object it is acting
upon, even though they share the same interface. This enables a system to be more flexible and
extensible, as new subclasses can be introduced without modifying the code that uses the
superclass interface, adhering to the Open/Closed Principle.
Question 4: During the requirements gathering phase of Object-Oriented Analysis, a "Use
Case" primarily serves to describe which of the following?
A. The internal algorithmic steps and data structures used by a specific class to process
information. B. The sequence of interactions between a system and external entities to achieve
a specific, observable goal of value. C. The physical deployment architecture of the software
components across various hardware nodes. D. The state transitions of a specific object in
response to internal and external events over its lifecycle.
CORRECT ANSWER: B. The sequence of interactions between a system and external entities to
achieve a specific, observable goal of value.
Rationale: A Use Case is a methodology in Object-Oriented Analysis used to capture functional
requirements. It describes a sequence of actions, including variants, that a system performs to
yield an observable result of value to a particular actor (an external entity interacting with the
system).
,Question 5: In a UML Class Diagram, what does a multiplicity of "1..*" on an association end
signify?
A. The associated class must have exactly one instance linked to the other class. B. The
associated class may have zero or one instance linked to the other class. C. The associated class
must have at least one instance, and potentially many instances, linked to the other class. 3.
The associated class can have any number of instances, including zero, linked to the other class.
CORRECT ANSWER: C. The associated class must have at least one instance, and potentially
many instances, linked to the other class.
Rationale: In UML, multiplicity defines the number of instances of one class that can or must be
associated with a single instance of another class. The notation "1..*" specifically means a lower
bound of 1 and an upper bound of many (unbounded), indicating that there must be at least
one instance, but there can be more.
Question 6: Which of the following UML relationships represents a strong form of
aggregation where the child object cannot exist independently of the parent object?
A. Dependency B. Association C. Aggregation D. Composition
CORRECT ANSWER: D. Composition
Rationale: Composition is a strong form of aggregation that implies a "whole-part" relationship
where the part (child) cannot exist without the whole (parent). If the parent object is
destroyed, the child object is also destroyed. It is represented by a solid diamond on the
parent's side of the association line.
Question 7: In the context of the SOLID design principles, the Single Responsibility Principle
(SRP) dictates that a class should have:
A. Only one reason to change, meaning it should encapsulate a single, well-defined functionality
or responsibility. B. The ability to be extended without modifying its existing source code,
relying on abstraction. C. The capability to be substituted with its subtypes without altering the
correctness of the program. D. Many client-specific interfaces rather than one general-purpose
interface.
CORRECT ANSWER: A. Only one reason to change, meaning it should encapsulate a single,
well-defined functionality or responsibility.
Rationale: The Single Responsibility Principle states that a class should have only one job or
responsibility. If a class has more than one responsibility, it becomes coupled, and a change to
one responsibility may impair the class's ability to fulfill the other, leading to fragile designs.
Question 8: When drawing a UML Sequence Diagram, what does a vertical dashed line
extending downwards from an object represent?
, A. The destruction of the object at a specific point in time. B. A synchronous message being sent
from one object to another. C. The lifeline of the object, representing its existence over time
during the interaction. D. An asynchronous message returning a value to the caller.
CORRECT ANSWER: C. The lifeline of the object, representing its existence over time during
the are interaction.
Rationale: In a Sequence Diagram, a lifeline is a vertical dashed line that represents the passage
of time and the existence of an object or participant during the interaction. Messages are
drawn as horizontal arrows between these lifelines to show the sequence of communication.
Question 9: In a UML Use Case Diagram, what is the semantic difference between an
«include» relationship and an «extend» relationship?
A. «Include» is optional and only happens under certain conditions, while «extend» is
mandatory and always executed. B. «Include» represents a mandatory insertion of another use
case's behavior, while «extend» represents optional, conditional behavior added to a base use
case. C. «Include» is used for generalizing actors, while «extend» is used for generalizing use
cases. D. «Include» denotes a temporal sequence, while «extend» denotes a spatial relationship
between use cases.
CORRECT ANSWER: B. «Include» represents a mandatory insertion of another use case's
behavior, while «extend» represents optional, conditional behavior added to a base use case.
Rationale: The «include» relationship indicates that the base use case explicitly incorporates
the behavior of the included use case (mandatory). Conversely, the «extend» relationship
indicates that the extending use case adds behavior to the base use case only under specific,
optional conditions defined by an extension point.
Question 10: Which Object-Oriented design metric is primarily used to measure the degree of
interdependence between software modules, with the goal of keeping this metric as low as
possible?
A. Cohesion B. Coupling C. Cyclomatic Complexity D. Inheritance Depth
CORRECT ANSWER: B. Coupling
Rationale: Coupling measures the degree of interdependence between software modules. Low
coupling is a sign of a well-structured computer system and a good design, as it means that
changes in one module have minimal impact on other modules, thereby enhancing
maintainability and testability.
Question 11: In Object-Oriented Analysis, an "Abstract Class" is best defined as:
A. A class that cannot be instantiated directly and is intended to be subclassed by other classes
to provide specific implementations. B. A class that contains only static methods and cannot
Analysis Study Guide 2025, Covering Object-Oriented
Systems Analysis Principles, UML Modelling Techniques
and Diagrams, Use Case and Class Diagram
Development, Object Identification and System Modelling,
Requirements Gathering and System Specification
Analysis, Software Development Life Cycle Integration,
Database and System Design Foundations, Encapsulation
Inheritance and Polymorphism Concepts, Real-World
Business System Modelling, Risk and Requirements
Validation Techniques, Practice Questions with Verified
Answers and Detailed Explanations, Step-by-Step UML
Diagram Construction Methods, Case Studies in System
Analysis, and Proven Strategies to Successfully Master
ICT2622 Object-Oriented Analysis
Question 1: In the context of Object-Oriented Analysis and Design, which of the following
best describes the primary purpose of encapsulation when designing a software system's
class architecture?
A. It allows a subclass to inherit all the public and private attributes of its parent class without
any restrictions. B. It bundles the data and the methods that operate on that data within a
single unit, while restricting direct access to some of the object's components. C. It enables a
single interface to represent different underlying forms of data, allowing methods to be used
interchangeably across diverse object types. D. It ensures that a class has only one reason to
change, thereby promoting high cohesion and low coupling across the entire system
architecture.
CORRECT ANSWER: B. It bundles the data and the methods that operate on that data within a
single unit, while restricting direct access to some of the object's components.
Rationale: Encapsulation is a fundamental object-oriented principle that involves bundling the
state (attributes) and behavior (methods) of an object into a single unit (a class) and restricting
direct access to some of the object's components. This is typically achieved through access
modifiers (like private or protected), which protect the internal state of the object from
unintended interference and misuse, thereby enhancing maintainability, security, and
modularity.
,Question 2: When modeling a software system using UML, which relationship between two
classes indicates that one class is a specialized version of another, inheriting its attributes and
operations?
A. Dependency B. Aggregation C. Generalization D. Realization
CORRECT ANSWER: C. Generalization
Rationale: Generalization is the UML relationship that represents inheritance, where a
specialized class (subclass or child) inherits the attributes and operations of a more generalized
class (superclass or parent). This relationship is depicted by a solid line with a hollow, closed
arrowhead pointing from the subclass to the superclass, signifying an "is-a" relationship.
Question 3: In Object-Oriented Analysis, polymorphism is best utilized in a system design to
achieve which of the following primary objectives?
A. To hide the internal implementation details of a class from other classes in the system. B. To
allow objects of different classes to be treated as objects of a common superclass, enabling
interchangeable behavior. C. To ensure that a class is instantiated only once throughout the
entire lifecycle of the application. D. To combine multiple interfaces into a single, simplified
interface for a complex subsystem.
CORRECT ANSWER: B. To allow objects of different classes to be treated as objects of a
common superclass, enabling interchangeable behavior.
Rationale: Polymorphism allows methods to do different things based on the object it is acting
upon, even though they share the same interface. This enables a system to be more flexible and
extensible, as new subclasses can be introduced without modifying the code that uses the
superclass interface, adhering to the Open/Closed Principle.
Question 4: During the requirements gathering phase of Object-Oriented Analysis, a "Use
Case" primarily serves to describe which of the following?
A. The internal algorithmic steps and data structures used by a specific class to process
information. B. The sequence of interactions between a system and external entities to achieve
a specific, observable goal of value. C. The physical deployment architecture of the software
components across various hardware nodes. D. The state transitions of a specific object in
response to internal and external events over its lifecycle.
CORRECT ANSWER: B. The sequence of interactions between a system and external entities to
achieve a specific, observable goal of value.
Rationale: A Use Case is a methodology in Object-Oriented Analysis used to capture functional
requirements. It describes a sequence of actions, including variants, that a system performs to
yield an observable result of value to a particular actor (an external entity interacting with the
system).
,Question 5: In a UML Class Diagram, what does a multiplicity of "1..*" on an association end
signify?
A. The associated class must have exactly one instance linked to the other class. B. The
associated class may have zero or one instance linked to the other class. C. The associated class
must have at least one instance, and potentially many instances, linked to the other class. 3.
The associated class can have any number of instances, including zero, linked to the other class.
CORRECT ANSWER: C. The associated class must have at least one instance, and potentially
many instances, linked to the other class.
Rationale: In UML, multiplicity defines the number of instances of one class that can or must be
associated with a single instance of another class. The notation "1..*" specifically means a lower
bound of 1 and an upper bound of many (unbounded), indicating that there must be at least
one instance, but there can be more.
Question 6: Which of the following UML relationships represents a strong form of
aggregation where the child object cannot exist independently of the parent object?
A. Dependency B. Association C. Aggregation D. Composition
CORRECT ANSWER: D. Composition
Rationale: Composition is a strong form of aggregation that implies a "whole-part" relationship
where the part (child) cannot exist without the whole (parent). If the parent object is
destroyed, the child object is also destroyed. It is represented by a solid diamond on the
parent's side of the association line.
Question 7: In the context of the SOLID design principles, the Single Responsibility Principle
(SRP) dictates that a class should have:
A. Only one reason to change, meaning it should encapsulate a single, well-defined functionality
or responsibility. B. The ability to be extended without modifying its existing source code,
relying on abstraction. C. The capability to be substituted with its subtypes without altering the
correctness of the program. D. Many client-specific interfaces rather than one general-purpose
interface.
CORRECT ANSWER: A. Only one reason to change, meaning it should encapsulate a single,
well-defined functionality or responsibility.
Rationale: The Single Responsibility Principle states that a class should have only one job or
responsibility. If a class has more than one responsibility, it becomes coupled, and a change to
one responsibility may impair the class's ability to fulfill the other, leading to fragile designs.
Question 8: When drawing a UML Sequence Diagram, what does a vertical dashed line
extending downwards from an object represent?
, A. The destruction of the object at a specific point in time. B. A synchronous message being sent
from one object to another. C. The lifeline of the object, representing its existence over time
during the interaction. D. An asynchronous message returning a value to the caller.
CORRECT ANSWER: C. The lifeline of the object, representing its existence over time during
the are interaction.
Rationale: In a Sequence Diagram, a lifeline is a vertical dashed line that represents the passage
of time and the existence of an object or participant during the interaction. Messages are
drawn as horizontal arrows between these lifelines to show the sequence of communication.
Question 9: In a UML Use Case Diagram, what is the semantic difference between an
«include» relationship and an «extend» relationship?
A. «Include» is optional and only happens under certain conditions, while «extend» is
mandatory and always executed. B. «Include» represents a mandatory insertion of another use
case's behavior, while «extend» represents optional, conditional behavior added to a base use
case. C. «Include» is used for generalizing actors, while «extend» is used for generalizing use
cases. D. «Include» denotes a temporal sequence, while «extend» denotes a spatial relationship
between use cases.
CORRECT ANSWER: B. «Include» represents a mandatory insertion of another use case's
behavior, while «extend» represents optional, conditional behavior added to a base use case.
Rationale: The «include» relationship indicates that the base use case explicitly incorporates
the behavior of the included use case (mandatory). Conversely, the «extend» relationship
indicates that the extending use case adds behavior to the base use case only under specific,
optional conditions defined by an extension point.
Question 10: Which Object-Oriented design metric is primarily used to measure the degree of
interdependence between software modules, with the goal of keeping this metric as low as
possible?
A. Cohesion B. Coupling C. Cyclomatic Complexity D. Inheritance Depth
CORRECT ANSWER: B. Coupling
Rationale: Coupling measures the degree of interdependence between software modules. Low
coupling is a sign of a well-structured computer system and a good design, as it means that
changes in one module have minimal impact on other modules, thereby enhancing
maintainability and testability.
Question 11: In Object-Oriented Analysis, an "Abstract Class" is best defined as:
A. A class that cannot be instantiated directly and is intended to be subclassed by other classes
to provide specific implementations. B. A class that contains only static methods and cannot
