Quiz 3

Question 1

Problems using java arrays?

Answer 1

Fixed length
Cannot accommodate extra elements once created
Memory is allocated during creation only, much before the elements are added

Question 2

Solution to java arrays?

Answer 2

ArrayLists

Question 3

Problem with array lists?

Answer 3

Cannot store primitive data types (int, double, char, bool)

Question 4

Solution to array list primitive problems?

Answer 4

Store their wrapper classes instead (interger, double, character, boolean)

Question 5

Unboxing?

Answer 5

Is the method of taking an integer object and assigning its value to a primitive int

Question 6

Boxing?

Answer 6

Is the method of taking a primitive int and assigning it to an integer object

Question 7

Is-a test?

Answer 7

A teacher is-a person
A student is-a person

Question 8

What is inheritance?

Answer 8

The ability of one class to adopt the data and attributes of other classes

Inheritance allows you to reuse methods that is already written to create more specialised versions of a class

Question 9

Super keyword

Answer 9

Super refers to a child’s parent class

Question 10

Method overriding?

Answer 10

Method in a subclass with same signature overrides method from base class
New method with same name with same signature

Question 11

final modifer?

Answer 11

to specify that a method cannot be overridden in a subclass

Question 12

Overloading?

Answer 12

New method in same class with same name but with different signature