Code generation issue with stream_mode field using anyOf

[Nicolas Peulvast (peulvast)]

Hi team!

I encountered a compilation error when generating Java server stubs from the agent-protocol OpenAPI specification using the jaxrs-spec generator (OpenAPI Generator version 7.16.0).

cannot find symbol
symbol: variable values
location: class com.ibm.ads.openapi.agent.protocol.model.Run

The stream_mode field in the Run > RunStream schemas uses an anyOf structure with a default value:

"stream_mode": {
    "anyOf": [
        {"$ref": "#/components/schemas/StreamMode"},
        {
            "items": {"$ref": "#/components/schemas/StreamMode"},
            "type": "array"
        }
    ],
    "default": "values"
}

The generator incorrectly interprets the default value "values" as a variable name rather than a string literal, producing:

private StreamMode streamMode = values;  // 'values' is undefined

Workaround I've found so far ...

I simplified the definition to use a direct reference without anyOf and removed the default value:

"stream_mode": {
    "$ref": "#/components/schemas/StreamMode",
    "title": "Stream Mode",
    "description": "The stream mode to use."
}

Question

Is there a recommended way to define a field that can accept either a single enum value or an array of enum values with a default value, that works correctly with the jaxrs-spec generator?
Or should the specification be updated to avoid this pattern?

Thanks,

Nicolas