oneOf in generated spring server return empty JSON

Q&A (please complete the following information)

• OS: RHEL 7 (docker)
• Browser: yandex broser
• Version: latest container (swagger ui)
• Method of installation: docker
• Swagger/OpenAPI version: 3.0.2

Content & configuration

Example Swagger/OpenAPI definition:

Path is:
  /choiceTest:
    post:
      operationId: "ChoiceTest"
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: "#/components/schemas/typicalRequest"
      responses:
        "200":
          content:
            application/json:
              schema:
                $ref: "#/components/schemas/checkChoice"

ComponentSchema is:
    checkChoice:
      type: "object"
      oneOf:
      - properties:
          integerValue:
            format: "int32"
            type: "integer"
      - properties:
          longValue:
            format: "int64"
            type: "integer"
      - properties:
          stringValue:
            type: "string"
      - properties:
          doubleValue:
            format: "double"
            type: "number"

Describe the bug you're encountering

if you define oneOF and generate a server. Then even if the value taken from the swagger ui is inserted correctly, an empty json will be returned

To reproduce...

Use swagger ui.

Steps to reproduce the behavior:

1. Define any type with one of.
2. Generate a spring server.
3. In controller define correct value

Expected behavior

Json with a valid value in response. (Actually it return {})

Screenshots

Start by reproducing the issue with the supplied OpenAPI 3.0.2 schema in Swagger UI and a generated Spring server. Inspect how the generated oneOf response is serialized, then compare it with a response using a non-oneOf schema; done means the valid selected value is returned as JSON instead of {}.