[3.0.7] Swagger codegen generated code misses method for certain media type

Description

I'm trying to build a REST api versioned by mediatypes using Swagger 3. I want to return different objects depending on the accept header within the request.

So I created a yaml file in http://editor.swagger.io and generated the server code (jaxrs-cxf). But the generated code always only contains a method for the first object type.

Swagger-codegen version

3.0.7

Swagger declaration file content or url

I broke it down to a fairly simple yaml file. When generating the server code, only one method is generated:

openapi: 3.0.2
info:
  title: pet test api
  description: testapi for mime based versioning
  version: 1.0.0
servers:
  - url: https://animal.com/pets
paths:
  /pet:
    get:
      tags: 
        - pets
      summary: pets
      description: get cat or dog
      responses: 
        '200':
          description: get specific pet
          content:
            application/cat+json:
              schema:
                $ref: '#/components/schemas/cat'
            application/dog+json:
              schema:
                $ref: '#/components/schemas/dog'
components:
  schemas:
    cat:
      type: object
      properties:
        id:
          type: integer
        name:
          type: string
    dog:
      type: object
      properties:
        name:
          type: string
        age:
          type: integer

My expectation would be to get at least two methods generated within main/java/io.swagger.api.impl.PetsApiServiceImpl.java

public class PetsApiServiceImpl implements PetsApi {
    /**
     * pets
     *
     * get cat or dog
     *
     */
public Cat petGet() {
        // TODO: Implement...

        return null;
    }

public Dog petGet() {
        // TODO: Implement...

        return null;
    }
}

But actually only one method is being generated:

public class PetsApiServiceImpl implements PetsApi {
    /**
     * pets
     *
     * get cat or dog
     *
     */
    public Cat petGet() {
        // TODO: Implement...

        return null;
    }

}

To be honest, this is the first time I use swagger.

So is my expectation wrong, and what I want to archive is simply not possible? Or is this a bug within the swagger codegen?

Thanks, Jan

Command line used for generation

java -jar swagger-codegen-cli.jar generate -l jaxrs-cxf -i catdog.yml

Run the reported java -jar swagger-codegen-cli.jar generate -l jaxrs-cxf -i catdog.yml command using the supplied OpenAPI document, then inspect main/java/io.swagger.api.impl.PetsApiServiceImpl.java. Trace how the two response media types are represented in the generated API and determine the supported behavior for this case. Done means the behavior is covered by an appropriate regression test or the issue is clearly documented as unsupported.