Mastering Class Design Patterns: A Practical Guide in JavaScript

From Observer to Strategy and Adapter, Unlock the Power of Reusable Code

Photo by Tatiana Zhukova on Unsplash

In the world of JavaScript, design patterns play a crucial role in crafting maintainable, scalable, and efficient code. These patterns serve as blueprints for solving common programming challenges, promoting code reusability and modularity.

In this article, we’ll explore three essential class design patterns: Observer, Strategy, and Adapter, providing up-to-date code examples to enhance your JavaScript skills.

1. Observer Pattern

The Observer pattern is a behavioral design pattern that establishes a one-to-many relationship between objects. It allows objects (observers) to be notified and updated automatically when the state of another object (subject) changes.

class Subject {
  constructor() {
    this.observers = [];
  }

  subscribe(observer) {
    this.observers.push(observer);
  }

  unsubscribe(observer) {
    this.observers = this.observers.filter(obs => obs !== observer);
  }

  notify(data) {
    this.observers.forEach(observer => observer.update(data));
  }
}

class Observer {
  update(data) {
    console.log(`Observer received data: ${data}`);
  }
}

const subject = new Subject();
const…