Design Patterns in Java for Beginners | GoF Introduction

In this video, we start the Design Patterns in Java series from the absolute foundation. Most developers hear terms like Singleton, Factory, Strategy, Observer, Adapter, Decorator, and Facade — but they often do not clearly understand why these patterns exist, what problem they solve, and when they should be avoided. In this introduction, we will understand what a design pattern really is, why the Gang of Four patterns became so important, and how design patterns help us write flexible, reusable, and maintainable Java code. This video is not just theory. We connect design patterns with real Java development, object-oriented programming, interfaces, inheritance, composition, polymorphism, and Spring Boot usage. In this video, you will learn: What is a design pattern? What design patterns are not History of Gang of Four design patterns The 4 essential elements of every pattern Creational, Structural, and Behavioral pattern families Class scope vs object scope Why “program to an interface” matters Why composition is often better than inheritance 8 common causes of redesign in software projects How to select the right design pattern When you should skip a pattern completely