CLASS NOTES PART 2

Question 1

What are objects?

Answer 1

Instance of a class

Question 2

What is a class?

Answer 2

Structure that contains data and methods

Question 3

Four Basic OOP Principles

Answer 3

1.) Encapsulation
2.) Inheritance
3.) Polymorphism
4.) Abstraction

Question 4

What is Encapsulation?

Answer 4

Protects the data inside of it

Question 5

What is Inheritance?

Answer 5

One object can re-use the code of another object through an IS-A relationship vs a HAS-A relationship.
1.) Strong relationship
2.) Fragile base class – changes to the
parent can break the behavior of it’s
children.
3.) Class Explosion

Question 6

What is Polymorphism?

Answer 6

Many shapes
Parameter overloading
add(int i1, i2){}
add(int i1, i2,int i3){}
Many objects with the same base class
can have different shapes
class Shape{ draw(){}}
class Circle extends Shape{ draw(){}}
class Square extends Shape{draw{}}

Question 7

What is Abstraction?

Answer 7

Any method that does anything is providing functionality that I don’t need to know about.