Book Inventory Management System

A Spring Boot application for managing book inventories, users, and transactions.

This project follows a strict layered architecture to ensure scalability and maintainability.

🚀 Tech Stack

• Language: Java 21+
• Framework: Spring Boot 4.x
• Data Access: Spring Data JPA (Hibernate)
• Database: MySQL
• Build Tool: Maven

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🏗 Project Structure & Standards

The project follows a specific package-level hierarchy under com.bookinventory.

Package	Purpose	Naming/Coding Rules
.model	Database Entities	Includes Entity, Junction, and Transaction tables.
.dto	Data Transfer Objects	Constraint: Must only have a DEFAULT constructor.
.dto.converter	Model-DTO Mapping	Must use public static methods: convert(Model) and convert(DTO).
.repository	Data Access Layer	Classes must end with Repository.
.service	Business Logic	Interfaces end with Service; Implementations end with Impl.
.api	Web Controllers	Annotated with @RestController; end with Controller.
.exception	Error Handling	Custom and Global classes; must end with Exception.

🌐 API & Routing Standards

All controllers must follow a strict annotation and naming pattern to keep the API predictable.

1. Annotations & Naming

• @RestController: Every controller must use this annotation (no standard @Controller).
• Naming: Class names must end with Controller (e.g., BookController).

2. Root URL Formatting

Every controller must define a root URL using @RequestMapping that includes a trailing slash.

Example:

@RestController
@RequestMapping("/user/") // Required trailing slash
public class UserController {
    // Endpoints here
}

📂 Folder Tree Visual

src/main/java/com/bookinventory/
├── api/             # Controllers (@RestController)
├── dto/             # Data Transfer Objects
│   └── converter/   # Static Model <-> DTO mappers
├── exception/       # Custom & Global Exception Handlers
├── model/           # JPA Entities
├── repository/      # JpaRepository Interfaces
└── service/         # Business Logic (Interface + Impl)