Java – Factory Design Pattern

Java – Factory Design Pattern

Introduction
Factory pattern is used in the scenerio where the project contains a super class and ‘n’ number of sub-classes, In which the subclass object is created depending on the data provided. This article touches the basics of Factory Design Pattern using some sample codes that contains an abstract class named “Vechicle”, Two sub classes named “Car” and “Bike” and a factory class named “FactoryVechicle”.



Abstract class – VechicleThis abstract class acts as a super class which contains a method named “ride()”.

1	package com.sample.patterns;

2

3	public abstract class Vechicle

4

5

{

6	public abstract String ride();

7

}

8

}

Subclass – Car, BikeThe sub classes “Bike” and “Car” extends the abstract class “Vechicle” and each provides the implementation for the “ride()” method.
Car.java

1	package com.sample.patterns;

2	public class Car extends Vechicle

3

{

4

@Override

5	public String ride()

6

{

7	return "Riding car is pleasant";

8

}

9

}

Bike.java

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print

01	package com.sample.patterns;

02	public class Bike extends Vechicle

03

{

04

05

@Override

06	public String ride()

07

{

08	return "Riding bike is thrill";

09

}

10

}

Factory class – FactoryVechicleThis class contains a static method named “getVechicleObject” which returns the subclass object based on the data provided.

01	package com.sample.patterns;

02

03	public class FactoryVechicle

04

{

05	public static Vechicle getVechicleObject(String name)

06

{

07	if(name.equalsIgnoreCase("Bike"))

08

{

09	return new Bike();

10

}

11

else

12

{

13	return new Car();

14

}

15

}

16

}

Test Class – FactoryTestThis class is used to test the Factory design pattern by passing the arguments to the method “getVechicleObject” of the “FactoryVechicle” class.

FactoryTest.java

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01	package com.sample.patterns;

02

03	public class FactoryTest

04

{

05	public static void main(String args[])

06

{

07	Vechicle bike = FactoryVechicle.getVechicleObject("Bike");

08	System.out.println(bike.ride());

09	Vechicle car = FactoryVechicle.getVechicleObject("Car");

10	System.out.println(car.ride());

11

}

12

}

The output of the preceding program will be displayed as the below,

1	Riding bike is thrill

2	Riding car is pleasant

Thats all folks, This article explains the basics of FactoryDesignPattern and if you find this article is useful to you, Dont forget to leave your valuable comments. Have a joyous code day.