Factory Design Pattern – Creating Objects the Smart Way

📘 Why This Blog?

When I first came across the Factory Design Pattern, it felt like magic. But with a bit of practical exploration, I realized it’s just a smart way to decouple object creation from usage.
This devblog is my attempt to help you understand the Factory Pattern the way I wish someone explained it to me.

📖 What is the Factory Pattern?

The Factory Pattern provides a way to delegate the instantiation logic to a separate method or class. Instead of using new in multiple places, we delegate it to a Factory that knows how to create different objects based on some input.

In simple terms: You say what you want, not how to create it.

🔍 Spotting a Factory Pattern

You might be looking at a Factory Pattern if you see:

• Code like: IEnemy enemy = EnemyFactory.getEnemy("orc");
• One interface or abstract class, but many concrete implementations.
• A centralized class responsible for returning the appropriate implementation.

🧪 Code Example – Enemy Factory

Step 1: Create an interface

public interface IEnemy { void attack(); } 

Step 2: Implement the interface in multiple classes

public class Orc implements IEnemy { public void attack() { System.out.println("Orc attacks with axe!"); } } public class Goblin implements IEnemy { public void attack() { System.out.println("Goblin throws dagger!"); } } 

Step 3: Create the Factory Class

public class EnemyFactory { public static IEnemy getEnemy(String enemyType) { if (enemyType.equalsIgnoreCase("orc")) { return new Orc(); } else if (enemyType.equalsIgnoreCase("goblin")) { return new Goblin(); } throw new IllegalArgumentException("Unknown enemy type"); } } 

Step 4: Use it in your code

public class Game { public static void main(String[] args) { IEnemy enemy1 = EnemyFactory.getEnemy("orc"); enemy1.attack(); IEnemy enemy2 = EnemyFactory.getEnemy("goblin"); enemy2.attack(); } } 

🧠 Personal Notes to Apply Factory Pattern

Start with usage:

IEnemy enemy = EnemyFactory.getEnemy("orc"); 

Then build everything around it:

• Create IEnemy interface
• Create Orc, Goblin, etc. classes that implement IEnemy
• Create EnemyFactory to return IEnemy objects

Keep the logic of what to return in one place – the factory.

✅ Benefits

• Centralized object creation logic
• Clean, readable code
• Easy to add new object types
• Loose coupling between client and concrete classes

🔗 More Examples

Check out more hands-on examples of the Factory Pattern here:

👉 Factory Design Pattern on GitHub

🧵 TL;DR

Factory Pattern is a smart way to delegate object creation.

You don’t worry about new – just ask the factory for what you need.

Made with ❤️ by syedyshiraz