How to generate code from an openapi file?

Question

is it possible to generate java code from the openapi definition file with quarkus? Or should I use an external tool ?

Answer 1

Have a look at https://github.com/OpenAPITools/openapi-generator. I don't think Quarkus can do that.
Quarkus could generate an openapi yaml file from your quarkus project, which you could again use for openapi client generation.
For that take a look here https://quarkus.io/guides/openapi-swaggerui