A robust, console-based Library Management System engineered with Python OOP.

Demonstrating core backend fundamentals: Abstract Classes, Exception Handling, Serialization, and modular code architecture.

📚 Library Management System (Python OOP)

A fully functional console‑based Library Management System built using Python OOP, with features like user roles, borrowing limits, ISBN validation, and persistent storage using pickle.

This project demonstrates strong fundamentals in:

• Object‑Oriented Programming
• Abstract Classes
• Exception Handling
• Serialization (Saving/Loading State)
• Input Validation (Regex)
• Clean, modular code structure

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🚀 Features

🧩 Book Management

• Add new books with ISBN validation (13‑digit format)
• Prevent duplicate book entries using custom exception
• Search books by title or author

👥 User Management

• Two user types:

  • Student (borrow limit: 3)
  • Staff (borrow limit: 5)

• Adds user with email and UAE phone number regex validation

📖 Borrowing System

• Users can borrow books only if:

  • They haven't reached their borrow limit
  • The book isn't already borrowed

• Custom exceptions for borrow limit violations

• Returning books updates the book status properly

💾 Save / Load System

• Save the entire library state to a file using pickle
• Load previously saved system state

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🏗️ Project Structure

LibrarySystem/
│── library.py              # Main library classes
│── main.py                 # Entry point with menu
│── README.md               # Documentation
│── saved_state.pkl         # (example saved file)

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📦 Installation

# Clone the repository
$ git clone https://github.com/<your-username>/library-system.git
$ cd library-system

# Run the project
$ python main.py

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🖥️ Usage

Once you run the script, the following menu will appear:

----- Library System -----
1. Add Book
2. Add User (Student/Staff)
3. Borrow Book
4. Return Book
5. Search Book
6. Save Library State
7. Load Library State
8. Exit

Follow the menu prompts to manage your library.

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🧪 Exception Handling Included

• InvalidISBNException – triggered when ISBN is not 13 digits
• BookAlreadyExistException – prevents duplicate books
• BorrowLimitExceededException – prevents users from exceeding borrow limits

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✔️ Example Input Validations

Field	Validation	Regex
ISBN	13 digits	^\d{13}$
Email	simple format check	^\w+@\w+\.\w{3}$
UAE Phone	+971 followed by 9 digits	^\+971\d{9}$

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📸 Demo

(Optional: you can later add screenshots of the console output here)

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🧱 Technologies Used

• Python 3
• OOP Principles
• ABC (Abstract Base Classes)
• Regular Expressions
• Pickle Module

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🤝 Contributing

Pull requests are welcome! For major changes, please open an issue first.

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⭐ Acknowledgment

Written as part of a Python OOP coursework project.

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🔗 GitHub Repository

Replace with your link:

https://github.com/mishal636/Library-Management-System-Python-OOP-