System Design & LLD Patterns

This repository contains System Design and Low-Level Design (LLD) examples implemented in Java.
It is intended as a reference for learning object-oriented design principles, design patterns, and real-world system design problems.

---

📖 Contents

🔹 Design Patterns Implemented

• Factory Pattern – Creating objects without exposing the creation logic.
• Decorator Pattern – Dynamically adding behavior to objects at runtime.
• Proxy Pattern – Controlling access to objects via a surrogate/proxy class.
• Observer Pattern – Defining one-to-many dependency for event-driven systems.
• Strategy Pattern – Defining interchangeable algorithms at runtime.
• Null Object Pattern – Avoiding null checks by using a default object.

🔹 System Design / LLD Examples

• BookMyShow – LLD of an online movie ticket booking system.
• Parking System – LLD of a parking lot management system.
• Log Processor – LLD of a logging system with different log levels.
• HashMap Internal Implementation – Simplified custom HashMap implementation in Java.

---

🛠 Tech Stack

• Language: Java
• IDE Support: IntelliJ IDEA (project contains .iml and .idea/)

---

⚡ Getting Started

1. Clone the Repository

git clone https://github.com/tajbaba999/System_design.git
cd System_design