Mediator Design Pattern | Build Chat Room | UML + Code | System Design

Welcome to Lecture 35 of the Ultimate Low-Level Design (LLD) Series by Coder Army! Seventh week for #lowleveldesign #systemdesign #8weeksLLdchallenge We are doing 8 weeks challenge and going to complete the whole course within the duration with quality content on Youtube. Let’s learn LLD like never before and attain advance level mastery on this subject. In this LLD session, we’re diving into the Mediator Design Pattern, one of the most powerful behavioral patterns for reducing tight coupling between classes. We’ll begin by understanding the chaos of direct communication (without mediator), and then introduce a central Mediator to streamline message passing, mute features, and private messaging among users. What you’ll learn: - The problem with peer-to-peer communication in real-world systems - How Mediator simplifies object interaction in large systems - Step-by-step implementation in C++ / Java - Realistic example of a Chat Room with: - User Registration - Broadcasting Messages - Private Messaging - Mute Functionality Join Coder Army Whatsapp Group: https://www.whatsapp.com/channel/0029Va6H0tbHVvTbcuT99Y1f Code and Notes: Github : https://github.com/adityatandon15/LLD Connect with Aditya Tandon Instagram : https://www.instagram.com/adityatandon2 LinkedIn : https://www.linkedin.com/in/adityatandon2 Twitter : https://x.com/adityatandon02z 00:00 Introduction 07:28 Chat Room Example 15:43 Code for bad design 22:10 Introducing Mediator UML 32:47 Code for Chat room with mediator 41:31 Standard UML Diagram 42:23 Mediator vs Observer pattern 46:08 Standard Definition & Real World Uses #MediatorPattern #DesignPatterns #LowLevelDesign #LLD #SystemDesign #ChatApp #ObserverPattern #CoderArmy #OOP #CPlusPlus #Java #ChatRoomLLD #ObjectOrientedDesign #CleanCode #SOLID #DataStructures #PrivateMessaging