Compx Exam prep

definition of recursion

a method/ function that calls itself

definition of a class

a blueprint of the fields and methods of objects

definition of an object

an instance of a class with its own state

overriding vs overloading

overriding changes inherited behaviour, overloading means writing a method with the same name but different parameters

what is polymorphism?

different classes responding differently to the same method call

what is composition?

a class containing another class as a field

what is aggregation?

represents the whole part

what is big-O notation

a measure of algorithmic growth rate

what is an array?

a fixed-size indexed collection

what is a constructor

a method that initialises an object

what is encapsulation?

restricting access to class data

what is the purpose of a constructor?

to initialise a new object fields when created

what does a static method mean?

it belongs to itself

what does overriding a method allow a sub class to do?

provide its own version of a base class

what is the purpose of an interface?

to define a contract of methods a class must implement

what does the ‘continue’ keyword do inside a loop?

skips to next iteration

what is a UML association?

a relationship showing that two classes interact

what does keyword ‘return’ do inside a metod?

ends the method and optionally gives a value

abstract vs virtual methods?

abstract methods have no code and have to be overridden, virtual methods have implementation and the option to be overridden

base class vs sub-class

base class is the parent and the sub-class is the child that inherits from the parent

what is an iteration?

how many times a loop is repeated

compile time error vs run time error

compile time errors are structural and found before a program runs, run time errors are found while the program runs

inheriting from a class vs an interface

you can only inherit from one class but can inherit from multiple interfaces

stack vs heap memory

value types and method call data are stored in stack, reference types are stored in heap