Crud Demo with Spring Boot using Swagger, JPA and H2 DB.
See also https://rieckpil.de/howto-crud-application-with-spring-boot-2-2-java-11-and-h2/
Run SpringbootCrudApplication.java to start
Goto http://localhost:8080/h2-console
Change JDBC URL to jdbc:h2:mem:testdb (user: sa, password: empty)
http://localhost:8080/api/books
Swagger UI: (http://localhost:8080/swagger-ui.html).