[JAVA] Inheritence without discriminator, is it possible ?

Description

I've tried doing inheritance without discriminator and I think something changed in the latest version as I find "example" online which work the way I wanted it, but it's not what I'm generating with the 2.2.3 SNAPSHOT.

From reading #2096 it feels like it is now impossible to generate inheritence without a discriminator.

    MyParent:
      type: object
      properties:
        code:
          type: string

    MyChild:
      type: object
      allOf:
        - $ref: '#/definitions/MyParent'
        - properties:
            label:
              type: string

public class MyParentApiBean   {
  @JsonProperty("code")
  private String code = null;
}

public class MyChildApiBean   {
  @JsonProperty("code")
  private String code = null;

  @JsonProperty("label")
  private String label = null;
}

If I add a discriminator I do get inheritance but also an extra field (the discriminator field)
In my use case I do not want discriminator as the 2 objects will be used on different API path so there is never the need to know which type it at de-serialization.
And I do not want to force people to add an extra attribut in their json.

The use case I've is I want to be able to define a method taking a MyParentApiBean and working with the code field be it MyParentApiBean or MyChildApiBean.
Right now I've to declare the attribut as an Object and do instanceof or duplicate code.

Swagger-codegen version

2.2.3-SNAPSHOT

Suggest a fix/enhancement

I understand the issue with multiple allOf inheritance, but that could be fixed with interface as suggested #5275
Or if there is a single allOf inheritance could be done still with inheritance.

Again thanks for your work.
Hope to have the time to give a hand soon.

Start by reviewing the inheritance behavior discussed in issues #2096 and #5275, then reproduce the supplied MyParent/MyChild schema with the 2.2.3-SNAPSHOT generator. Trace the Java model generation path and compare output with and without a discriminator. Done means the single-allOf case supports the requested parent-child relationship without requiring an extra discriminator property, with regression coverage for the generated models.