Object-oriented design principles in LLD - Architecture Diagram

System Overview - Object-oriented design principles

This system demonstrates the core object-oriented design principles that help build flexible, reusable, and maintainable software. It shows how components like classes and objects interact following principles such as encapsulation, inheritance, polymorphism, and abstraction.

Architecture Diagram

User
  |
  v
Client Code
  |
  v
+-------------------+
|   Abstract Class   |
+-------------------+
      /      \
     /        \
+-------+  +---------+
|Class A|  | Class B |
+-------+  +---------+
     |          |
     v          v
+-------------------+
|   Interface(s)    |
+-------------------+

Components

User

actor

Interacts with the system by using client code

Client Code

component

Uses objects and calls methods following design principles

Abstract Class

class

Defines common interface and shared behavior for subclasses

Class A

class

Concrete implementation inheriting from Abstract Class

Class B

class

Another concrete implementation inheriting from Abstract Class

Interface(s)

interface

Defines contracts that classes implement to ensure polymorphism

Request Flow - 6 Hops

User → Client Code

Client Code → Abstract Class

Abstract Class → Class A or Class B

Class A or Class B → Interface(s)

Class A or Class B → Client Code

Client Code → User

Failure Scenario

Component Fails:Class A or Class B

Impact:If a concrete class implementation fails, the client code cannot complete the requested operation correctly.

Mitigation:Use polymorphism to switch to another class implementation or handle errors gracefully in client code.

Architecture Quiz - 3 Questions

Which component defines the common behavior that subclasses share?

A Interface(s)

B Abstract Class

C Client Code

D User

Design Principle

This architecture shows how object-oriented design principles like abstraction, inheritance, and polymorphism help build flexible systems. Abstract classes define shared behavior, interfaces enforce contracts, and concrete classes provide specific implementations. This separation allows easy extension and error handling.