what is encapsulation?
- all information about each object is in one location (1 class)
- variables are private with setter and getter methods to access/change them
pros of encapsulation?
- more security/privacy
- more organized
- no repeat of code (less redundant)
- easier to manage project (abstraction)
definition of inheritence
subclasses and superclasses
- classes can inherit attributes and methods from other classes
overloading
same method name, different parameters
overriding
same method name & parameters, in subclass/super class
polymorphism?
- static - overloading & overiding
- dynamic - assigning subclass instance to superclass reference
what is constructor
method that:
1. has same name as class name
2. no return type
what are 3 components of object
- name/identifier
- variables/attributes
- behaviours/instance methods
what are 3 components of classes
- variables / field (data / property / attribute / state)
a. normal field (aka. instance method)
b. static field (aka. class variable) - constructor
- method/behaviour
pros + cons of oop
pros:
1. encapsulation
- no repeat of code (less redundant)
- more security
- modularity
- abstraction
- polymorphism
- more code flexibility and reusability - inheritence
- attributes can be shared among classes
cons:
- not good for small projects
- learning curve
abstraction
hiding certain details and only showing essential info
modularity
breaking down program into smaller pieces so that changing one part of code doenst affect entire program
types of relationships (+ symbols)
- association
- uses/dependency (arrow ->)
- is-a (arrow with not coloured in head)
- has-a (aggregation (non-coloured rhombus), composition (shaded rhombus))
