Project: Online Book Store API

Objective: Implement a RESTful API for an online book store using Java and Spring Boot. The API should allow users to perform CRUD (Create, Read, Update, Delete) operations on books and authors.

Requirements:

1. Create a new Spring Boot project using Spring Initializr. Include the following dependencies: Web, JPA, and H2.
2. Set up the project with the following structure:
   • model package: containing the domain model classes (e.g., Book, Author)
   • repository package: containing the repository interfaces extending JpaRepository
   • service package: containing the service classes for business logic
   • controller package: containing the REST API controllers
   • exception package: containing custom exception classes
   • dto package: containing the data transfer objects used in the API
3. Implement the domain model:
   • Book class: should have fields for id, title, isbn, publishDate, price, and an Author relationship (ManyToOne)
   • Author class: should have fields for id, name, email, and a list of Book relationships (OneToMany)
4. Implement the repositories:
   • BookRepository interface: should extend JpaRepository<Book, Long>
   • AuthorRepository interface: should extend JpaRepository<Author, Long>
5. Implement the services:
   • BookService class: should contain methods for creating, updating, deleting, and retrieving books
   • AuthorService class: should contain methods for creating, updating, deleting, and retrieving authors
6. Implement the REST API controllers:
   • BookController class: should handle HTTP requests for CRUD operations on books
   • AuthorController class: should handle HTTP requests for CRUD operations on authors
7. Implement the data transfer objects (DTOs) for the API:
   • BookDTO: should contain fields for id, title, isbn, publishDate, price, and an Author relationship
   • AuthorDTO: should contain fields for id, name, and email
8. Implement exception handling:
   • Create custom exceptions (e.g., ResourceNotFoundException, BadRequestException)
   • Implement a global exception handler using @ControllerAdvice to handle exceptions and return appropriate HTTP response status codes
9. Configure an H2 in-memory database for the application.
10. Write unit tests for the service classes using JUnit and Mockito.
11. (Optional) Implement API documentation using Swagger or OpenAPI.

Deliverables:

• A fully functional Spring Boot project, including source code and tests
• A README file explaining how to build and run the project, as well as any design decisions made

When submitting your project, make sure to include all the necessary files in a single archive (e.g., ZIP or TAR) and provide clear instructions for building and running your application. Good luck!