Inventory Management System

A comprehensive Spring Boot application for managing product inventory and suppliers with a modern web interface and RESTful API.

Technologies Used

• Java 21+ - Core programming language
• Spring Boot 6.x - Application framework
• Spring Web - RESTful web services
• Spring Security - Authentication and authorization
• Spring Data JPA - Data persistence layer
• Thymeleaf - Server-side template engine for web UI
• H2 Database - In-memory database for development
• Maven - Dependency management and build tool
• Bean Validation - Input validation
• Spring Scheduling - Automated tasks

Architecture & Features

Core Features

• Product Management: CRUD operations for products with stock tracking
• Supplier Management: Complete supplier information management
• Low Stock Alerts: Automated monitoring and notifications
• User Authentication: Role-based access control (ADMIN/STAFF)
• Web Dashboard: Real-time inventory overview
• RESTful API: Complete API for external integrations

Security Implementation

• Role-based Access Control:
  • ADMIN: Full CRUD access to all resources
  • STAFF: Read access to products and suppliers
• HTTP Basic Authentication
• Method-level Security: Different permissions for different HTTP methods
• CSRF Protection: Configured for API usage

Data Models

• Product: Name, quantity, price, low stock threshold, supplier relationship
• Supplier: Name, email, phone contact information
• Many-to-One Relationship: Products linked to suppliers

Setup & Installation

Prerequisites

• Java 21 or higher
• Maven 3.9+
• Any IDE (IntelliJ IDEA, Eclipse, VS Code)

Installation Steps

1. Clone the repository

   git clone <your-repository-url>
   cd InventoryManagementSystem

2. Build the project

   mvn clean install

3. Run the application

   mvn spring-boot:run

4. Access the application

   • Web Interface: http://localhost:8080
   • H2 Database Console: http://localhost:8080/h2-console
   • API Base URL: http://localhost:8080/product or http://localhost:8080/supplier

Usage Guide

Web Interface

Dashboard (/)

• Overview of total products and suppliers
• Low stock alerts with highlighted items
• Recent products display
• Navigation to detailed views

Products Page (/products)

• Complete product listing
• Visual indicators for low stock items
• Product details including supplier information

Suppliers Page (/suppliers)

• Complete supplier directory
• Contact information display

REST API Endpoints

Authentication

Use HTTP Basic Authentication with these credentials:

• Admin User: username: admin, password: admin
• Staff User: username: staff, password: staff

Product Endpoints

GET    /product              # Get all products
GET    /product/{id}         # Get product by ID
POST   /product              # Create new product (ADMIN only)
PUT    /product/{id}         # Update product (ADMIN only)
DELETE /product/{id}         # Delete product (ADMIN only)
GET    /product/low-stock    # Get low stock products

Supplier Endpoints

GET    /supplier             # Get all suppliers
GET    /supplier/{id}        # Get supplier by ID
POST   /supplier             # Create new supplier (ADMIN only)
PUT    /supplier/{id}        # Update supplier (ADMIN only)
DELETE /supplier/{id}        # Delete supplier (ADMIN only)

Sample API Requests

Create a New Product (Admin Required)

POST /product
Content-Type: application/json
Authorization: Basic YWRtaW46YWRtaW4=

{
    "name": "Laptop Computer",
    "quantity": 50,
    "price": 999.99,
    "lowStockThreshold": 5,
    "supplier": {
        "id": 1
    }
}

Create a New Supplier (Admin Required)

POST /supplier
Content-Type: application/json
Authorization: Basic YWRtaW46YWRtaW4=

{
    "name": "Tech Supplies Inc",
    "email": "contact@techsupplies.com",
    "phone": "+1-555-0123"
}

Database Configuration

The application uses H2 in-memory database with file persistence:

spring.datasource.url=jdbc:h2:file:./data/mydb
spring.h2.console.enabled=true
spring.h2.console.path=/h2-console

Database Console Access:

• URL: http://localhost:8080/h2-console
• JDBC URL: jdbc:h2:file:./data/mydb
• Username: sa
• Password: (leave empty)

Automated Features

Low Stock Scheduler

• Runs every 5 minutes
• Monitors products below their low stock threshold
• Logs alerts to console
• Location: LowStockScheduler.java

Project Structure

src/
├── main/
│   ├── java/com/example/inventorymanagementsystem/
│   │   ├── controller/          # REST controllers and web controllers
│   │   ├── service/             # Business logic layer
│   │   ├── repository/          # Data access layer
│   │   ├── model/               # Entity classes and DTOs
│   │   ├── security/            # Security configuration
│   │   ├── exception/           # Custom exceptions and handlers
│   │   └── component/           # Scheduled tasks and components
│   └── resources/
│       ├── templates/           # Thymeleaf HTML templates
│       ├── static/             # Static web assets
│       └── application.properties
└── test/                       # Test classes

Security Features

• Password Encryption: BCrypt password encoding
• Role-based Authorization: Method-level security
• CSRF Protection: Configured for API usage
• HTTP Security: Secured endpoints with proper authentication

Exception Handling

Global exception handling with custom exceptions:

• ProductNotFoundException
• SupplierNotFoundException
• DuplicateProductException
• DuplicateSupplierException

Future Enhancements

• Add Unit Tests
• Add pagination for large datasets
• Implement advanced search and filtering
• Add email notifications for low stock
• Implement file upload for bulk operations

---

Note: This is a demonstration project showcasing Spring Boot, Spring Security, Spring Web, and modern web development practices in Java.