Java: Why Strategy Pattern is Important

Strategy pattern explained simply with real world examples

Strategy Pattern is just a fancy way of saying: “Let’s keep the core logic the same, but allow behavior to change easily by plugging in different pieces.”

Instead of writing a bunch of if-else or duplicating code for every small change in behavior, you define different strategies (as classes) and swap them as needed. It’s clean, flexible, and helps avoid messy code.

In this post we will learn it in simple way.

Situation: You’re Building a Payment System

You’ve got a PaymentService that supports credit card payments.

So you write:

public void pay(String method) {
    if (method.equals("creditcard")) {
        // handle credit card logic
    }
}

Then… Feature Creep Happens

• Add PayPal
• Add UPI
• Add Crypto (because your PM is now a Bitcoin bro)
• Add Apple Pay, Wallets, NetBanking…

So now your method becomes:

if (method.equals("creditcard")) {
    // credit card logic
} else if (method.equals("paypal")) {
    //…