Quite a lot of dependencies had to be upgraded. Java 11 is from 2018, and a lot has happened in 4 years.
-Upgraded Spring boot, and numerous third party libraries required by upgrade to Java 17. -Added @EqualsAndHashCode(callSuper=true) to no.deichman.euler.api.resource.jsonapi.vos.* classes. -Minor code improvements allowed by Java 17 and the Java language (like method ref, which was supported by Java 11 as well). -Replaced springfox with springdoc-openapi, since springfox does not support latest versions of Spring boot, and the project is dead in the last 2 years.