Class and inheritance

Ruby
1

Hi All,

I am not a programmer, yet. I am trying ruby on for size, most things
fit ok, but Classes are puzzling me.

class Stats
2

Classes in any OOP (object orientated language) follows the same basic
laws
of application.

A class would be the actual application or legal body of code. It must
be
noted that within a class body you can define class methods and instance
methods. This is what allows the application to actually function or
operate.

Ruby EXAMPLE:

class Greeter

def initialize(name)
@name = name
end

def say(phrase)
puts "#{phrase}, #{@name}"

end
end

g1 = Greeter.new(“Fred”)
g2 = Greeter.new(“Wilma”)

g1.say(“Hello”) #=> Hello, Fred
g2.say(“Hi”) #=> Hi, Wilma

Java EXAMPLE:

class HelloWorld {
public static void main(String [] args) {

System.out.println(“hello world!!!”);

Inheritance is the concept of a child class (sub class) automatically
inheriting the variables and methods
defined in its parent class (super class) This is known as inheritence.

EXAMPLE:

The Shape class would be the parent class, and from that the circle,
square, and rectangle classes would be created or inherited.

The Human class would be the the parent class, and from that the
man,
and woman classes would be created or inherited.

*Super class (Parent class) *
– Any class above a specific class in the class hierarchy.

Sub class (Child class)
– Any class below a specific class in the class hierarchy.

*In Ruby

*Class definitions start with the keyword class followed by the class
name
(which
must start with an uppercase letter).

Below is a class called MyClass.

class MyClass
def m1 # this method 1 is public
end

protected
def m2 # this method 2 is protected
end

private
def m3 # this method 3 is private
end
end