Week 9

Question 1

Software Development Lifecycle

Answer 1

Requirements
Design
Implementation
Testing
Maintenance

Question 2

How to Design Software

Answer 2

1. Modelling: Identify concepts and relations
2. Apply good architecture
3. Use appropriate data structures
4. Use design patterns when appropriate
5. Refactor

Question 3

Grammatical Parsing - Nouns

Answer 3

Class if it has multiple attributes / operations and they are common to all instances
otherwise: attribute of class

Question 4

Grammatical Parsing - Adjective

Answer 4

SubClass, Attribute
subclass: if adjective would imply different or additional operations or behavior or different adjectives imply different attributes

Question 5

Grammatical Parsing - Verb

Answer 5

Method: contains, has , is , uses, consists

Question 6

Is-a relationship types

Answer 6

Generalization: Generally inheritance, both can exist on their own. One class specialization of other
Realization: Implementation or inheritance of abstract class. Interface A has no notion of existence without being a specific tp of object B. E.g. Animal. If I say draw an animal I do not know what to draw -> realization.
If I ask to draw a person, I know what to draw -> Generalization

Question 7

has-a relationship types

Answer 7

Aggregation: one class is part of the other but they can exist idependently
Composition: one class part of the other. Cannot exist without the class to which it belongs

Question 8

uses relationship

Answer 8

Dependency
E.g. uses an instance of other class as input

Question 9

public abstract class Animal {}

public abstract class Mammal extends Animal {}

public class Dog extends Mammal {}

public class Cat extends Mammal {}

Answer 9

Realization relationship bw. all three

Although Mammal “extends” Animal in Java, Animal is an abstract class and thus cannot be realized on its own; therefore, a “realization” relationship is correct. The same holds true for Dog/Cat and Mammal, because Mammal is an abstract class as well.