chapter 6

Question 1

What is software design?

Answer 1

Software design involves specifying the structure of a software system without implementing the complete code.

Question 2

The most common design approach is ________

Answer 2

Object-Oriented,

Question 3

How is Object-Oriented structure is usually represented?

Answer 3

by Classes and by Class interactions

Question 4

What does software design transition from _______ to ______ ?

Answer 4

• “what” the system must do to
• “how” the system will do it.

Question 5

How are nouns and verbs utilized in the design process?

Answer 5

• Nouns are potential classes, objects, and fields [ student, grade, order, registration form ]
• verbs are potential methods or responsibilities of a class. [ register, encode grade, submit order ]

Question 6

What do relationships between nouns in design signify?

Answer 6

Relationships between nouns in design represent potential interactions, such as containment, generalization, or dependence.

• Student registers for Course
• customer orders pizza

Question 7

What questions does the design process aim to answer?

Answer 7

The design process seeks to answer questions like:

• Which nouns should be classes?
• Which ones become fields?
• What verbs should be methods?
• What interactions exist between classes?

Question 8

What is CRC, and how is it used to identify classes?

Answer 8

CRC stands for Class-Responsibility-Collaborators.

It helps identify classes by creating cards where :

• the class name is on top,
• followed by responsibilities (problems to be solved) and
• collaborators (classes that receive messages).

Question 9

What are the types of classes in CRC?

Answer 9

• Entity class
• Boundary class
• Control class

Question 10

_______ is a.k.a domain class

Answer 10

Entity class

Question 11

Entity class are the most important classes.

Answer 11

t

Question 12

entity class exists in the ______

Answer 12

problem domain. E.g student, course

Question 13

________ a class that exists on a system’s automation boundary [ web page, input window ]

Answer 13

Boundary class or view class

Question 14

what is a Control class?

Answer 14

Is a class that mediates between boundary classes and entity classes, acting as a switchboard between the view layer and domain layer

Question 15

_______ takes an event from boundary
class and calls the Entity class?

Answer 15

Control class

Question 16

Why do we create CRCs for classes that collaborate with the primary object class?

Answer 16

To complete a use case, CRCs for collaborating classes are created by asking questions about their responsibilities and the information they need to fulfill those responsibilities.

Question 17

_______ represents a collection of similar object in CRC?

Answer 17

A class

Question 18

_______ is something that a class knows or does in CRC

Answer 18

responsibility

Question 19

________ is another class that a class interacts with to fulfill its responsibilities in CRC?

Answer 19

collaborator

Question 20

What is the purpose of noun analysis from requirements?

Answer 20

Noun analysis from requirements helps identify essential elements in a system by focusing on nouns and their attributes.

UNIVERSITY
- have records of student and staff
- records = id, name, # no, …
- Subjects
- Salary …

Question 21

What is A UML class diagram?

Answer 21

A picture that Shows classes and relationships among them.

Question 22

What elements are Not represented in a UML class diagram?

Answer 22

– details of how the classes interact with each other
– algorithmic details; how a particular behavior is implemented

Question 23

What is meant by flexibility in UML class diagrams?

Answer 23

• Same class can be modeled in 4 different ways:
  – With no attributes or operations shown
  – With only the attributes shown
  – With only the operations shown
  – With both the attributes and operations shown

Question 24

______ is always the first component of the class box

Answer 24

The name of the class

Question 25

_______ is a property of a class

Answer 25

Attribute
Circle (centreX, centreY)

Question 26

_________ is sth that a class can do?

Answer 26

operation

Question 27

______ begins below a line separating them from class name and ______ below a line separating them from the attributes?

Answer 27

• attributes
• operations

Question 28

_______ specifies the extent to which other classes can use a given class’s attributes or operations?

Answer 28

Visibility

Question 30

What are the Three levels of visibility?

Answer 30

*public level
*protected level
*private level

Question 31

In _________ level is usability open only to classes that inherit from original class?

Answer 31

protected

Question 32

What does class multiplicity specify in a class?

Answer 32

Class multiplicity specifies the number of instances (objects) of that class that can exist simultaneously.

Question 33

What are the different types of relationships between classes?

Answer 33

• Association (delegation),
• Generalization (inheritance),
• Realization (interfaces),
• Dependency.

Question 34

How is Association represented between classes?

Answer 34

Association is a link.
- represented by a solid line between classes, with an example being “A Person works for a Company.”

Question 35

What are Association Properties?

Answer 35

• Name – Name of the association
• Role – The specific role of the association
  
  • employee | employer
• Multiplicity – Indicates the number of objects that are connected
• Type – Plain association, aggregation, composition
• Direction – Direction can also be shown for a association

Question 36

How is Multiplicity used in Association?

Answer 36

specify the number of links that can exist between instances (objects) of the associated classes.

Question 37

Multiplicity can be expressed as?

Answer 37

• Exactly one - 1
• Zero or one - 0..1
• Many - 0..* or *
• One or more - 1..*
• Exact Number - e.g. 3..4 or 6
• Or a complex relationship – e.g. 0..1, 3..4, 6..* would mean
  any number of objects other than 2 or 5

Question 38

An association that connects a class to itself is
called a _________

Answer 38

self association.

Question 39

what are the 2 types of association?

Answer 39

• aggregation
• composition

Question 40

explain aggregation.

Answer 40

• “is part of” / “Has a”
  ■ Unidirectional/not vice versa
• clear white diamond
• collage | teacher

Question 41

explain composition.

Answer 41

• “is entirely made of“ / “Contained”
  ■ stronger version of aggregation
  ■ the parts live and die with the whole
  ■ black diamond
• book | page

Question 42

explain Generalization (Inheritance).

Answer 42

• Child class is a special case of the parent class
• Animal [cat , dog ]

Question 43

Inheritance - Implementation?

Answer 43

public class Animal {
}

public class Cat extends Animal {
}

public class Dog extends Animal {
}

Question 44

The relationship between a class and an interface is called ________

Answer 44

realization

Question 45

explain an interface.

Answer 45

• Interface is a class with no attributes, only method signatures
• «interface» Animal
  • getSound()

■ Classes can implement the methods
■ Relationship Represented by a dashed, white arrow

Question 46

What is Dependency?

Answer 46

• Explains that Change in specification of one class can change the other class
• can also be used to show relationships between classes and objects.

Question 47

______ classes are left out from UML class diagram since Including them makes the diagram complex?

Answer 47

Boundary classes