📚 LIBRARY MANAGEMENT SYSTEM (CLI-BASED)

A command-line Library Management System built using Java 17, Maven, and Gson to demonstrate core Java concepts including OOP, collections, file handling, and JSON persistence.

🚀 Features

Add new books

List all books

Borrow a book

Return a book

Persistent storage using JSON

Auto-increment book IDs

Data loads automatically on startup

🛠️ Tech Stack

Java 17

Maven

Gson (JSON serialization/deserialization)

File I/O

Collections Framework (ArrayList)

Project Structure

LibraryMangmt/
│── pom.xml
│── src/
│   └── main/
│       └── java/
│           └── com/library/
│               ├── LibraryApp.java     (CLI Layer)
│               ├── Library.java        (Business Logic)
│               └── model/
│                   └── Book.java       (Model Class)

🧠 Architecture Overview

User (CLI Input)
        ↓
LibraryApp (Menu & Input Handling)
        ↓
Library (Business Logic & Operations)
        ↓
Book (Data Model)
        ↓
library.json (Persistence using Gson)

💾 Persistence Strategy

The application uses Gson to serialize the entire Library object into a JSON file.

Example library.json:

{
  "books": [
    {
      "id": 1,
      "title": "The Great Gatsby",
      "author": "F. Scott Fitzgerald",
      "available": false,
      "borrower": "Alice"
    }
  ],
  "nextId": 2
}

▶️ How To Build & Run

1️⃣ Clone the repository

git clone https://github.com/your-username/library-management-cli.git
cd library-management-cli

2️⃣ Build the project

mvn clean package

3️⃣ Run the application

Option A – Using Maven:

mvn exec:java -Dexec.mainClass="com.library.LibraryApp"

Option B – Run test_cli.bat:

test_cli.bat

📋 Sample CLI Menu

1. Add Book
2. List Books
3. Borrow Book
4. Return Book
5. Save
6. Exit

🎯 Concepts Demonstrated

Object-Oriented Programming (OOP)

Encapsulation

Separation of Concerns

Collections (ArrayList)

File Handling

JSON Serialization & Deserialization

Maven Build Lifecycle