Updated: 2017-04-17 17:33:02 CST +08

Object Oriented Programming

Basic

Visibility

Object SubClass SelfClass
public v v v
protected x v v
private x x v

Class

  • Constructor
  • Field
    • variable
    • constant
  • Method
    • Regular
    • depends on object
    • Static
    • depends on class
  • Destructor

Encapsulation

don’t operate data directly, use methods by parameters and arguments:

  • Getter, Accessors
  • Setter, Mutator

Inherited

  • IS-A
    • Is a Dog an Animal?
  • HAS-A
    • Dog has a Height.

Polymorphism

SubClass can override SuperClass methods, and be used when it’s declared as a SuperClass object.

Abstract Class

  • It’s like “theory of Forms”(Plato) in philosophy. - Dino Lai
  • use the power of Polymorphism without the work.
  • all the method in abstract should be abstract.
  • no abstract fields.

Interface

  • It’s like contract with employee and employer. - Dino Lai
  • Only declares methods to be implemented.