Class and Object

• Definition of Class

: Class is definition of object.

• Usage of Class

: Class is used for creating object.

Class	Object
Product blueprint	Product
(Metaphor)붕어빵 기계	붕어빵

• Components of Object : Properties and Function

Object = Property(Variable) + Function(Method)

class Tv {
    //Variable(=>Property)
    String color;
    boolean power;
    int channel;
    
    //Method(=>Function)
    void power() {power = !power;}
    void channelUp() {channel++;}
    void channelDown() {channel--;}
}

• Object and Instance

Object : Representative general terms of every Instance.

Instance : Created Object which is from specific Class.

Class ->(Instance화)->Instance(Object)

• Summary

1. Why need Class? To create Object.

2. Why need Object? To use Object.

3. What does using Object mean? To use properties and function of Object.