CRUD stands for Create, Read, Update and Delete, the four basic operations performed on application data.In REST, each operation is mapped to an HTTP method (POST, GET, PUT/PATCH, DELETE) on a resource URL such as /api/students.It is used because it gives every client (browser, mobile app, Postman) one standard, predictable way to manage data.Spring Boot implements it with @RestController, a service layer and a JPA repository that talks to MySQL.
Features
- One URL per resource, with the HTTP method deciding the action
- Standard status codes: 201 Created, 200 OK, 204 No Content, 400, 404, 409
- JSON request and response bodies
- Validation of input and duplicate-email checks
- No SQL needed, since JPA generates the queries.
CRUD represents the fundamental operations (Create, Read, Update, Delete) mapped directly to standard HTTP methods like POST, GET, PUT/PATCH, and DELETE on a unified resource URL. Spring Boot implements this architecture using @RestController, a service layer, and JPA repositories to provide clients with a predictable, JSON-driven interface backed by automated queries and HTTP status codes. For an example illustrating these core concepts in detail, refer to https://javaplanet.io/frameworks/spring-boot/rest-fundamentals/.