Given scan urls are empty, set urls in the configuration

I have the following dependencies in my jax-rs app:

https://mvnrepository.com/artifact/io.swagger.core.v3/swagger-annotations/2.0.6
https://mvnrepository.com/artifact/io.swagger.core.v3/swagger-core

public class RestApplication extends Application {
  
  @Override
  public Set<Class<?>> getClasses() {    
    Set<Class<?>> classes = new HashSet<>();
   
    classes.add(RandomImpl.class); //Interface Implementation without JaxRS annotation
    classes.add(OpenApiResource.class);
    classes.add(AcceptHeaderOpenApiResource.class);
    return classes;
  }
}

Now when I try to access the openapi.json I get the following warning:

given scan urls are empty. set urls in the configuration

I guess this is because I am registering the implementation of interface classes which hold the annotation but I can't obviously register the interfaces itself.

Just under this warning I get the following exception:

Exception Handling request to /openapi.json: org.jboss.resteasy.spi.UnhandlesException: java.lang.NoSuchMethodError: com.google.common.collect.Sets$SetView.iterator()Lcom/google/common/collect/UnmodifiableIterator;

Any help is appreciated! Thanks.

Start with the RestApplication.getClasses() entry point and the registered OpenApiResource and AcceptHeaderOpenApiResource classes. Reproduce the /openapi.json request using the listed swagger-annotations and swagger-core dependencies, then trace the empty scan-URL warning and NoSuchMethodError to determine whether the configuration or dependency versions are responsible. Done means the cause and a reproducible fix are documented.