Backend Engineering #3.2 — Inheritance, Composition & Polymorphism

In this session, we continue OOP from a backend engineering perspective and understand three important concepts that directly influence how we design backend code. Topics covered: Inheritance — understanding the “IS-A” relationship Composition — understanding the “HAS-A / USES-A” relationship Inheritance vs Composition Why composition is often more flexible in backend systems Polymorphism — same interface, different behavior Runtime polymorphism with practical payment examples Interfaces and interchangeable implementations How these concepts appear in real backend architecture Coupling and why loosely coupled code is easier to change We use practical backend examples instead of generic Animal/Dog examples to understand how these concepts actually show up in real applications. This is Part 2 of Session 3. Part 1 covered: OOP basics Encapsulation Abstraction PPT Link: https://docs.google.com/presentation/... Want to join the free live class? Visit here: https://forms.gle/GwkkbGQ7typfBy9A8 Next Session → SOLID Principles + Springboot basics #BackendEngineering #Java #SpringBoot #OOP #ObjectOrientedProgramming #SoftwareArchitecture #SystemDesign