[BUG][Java][microprofile] oneOf interface ignores useJakartaEe for @Generated annotation

[svifred]

Bug Report Checklist

• Have you provided a full/minimal spec to reproduce the issue?
• Have you validated the input using an OpenAPI validator?
• Have you tested with the latest master to confirm the issue still exists?
• Have you searched for related issues/PRs?
• What's the actual output vs expected output?
• [Optional] Sponsorship to speed up the bug fix or feature request (example)

Description

With the Java generator, the microprofile library, Jackson serialization, and useJakartaEe=true, enabling useOneOfInterfaces=true generates the oneOf interface with @javax.annotation.Generated rather than @jakarta.annotation.Generated.

This occurs with both useSealedOneOfInterfaces=false and useSealedOneOfInterfaces=true. The sealed option is not the cause; both modes use the shared oneOf interface template.

This makes generated models fail to compile in a Jakarta-only application, including Quarkus 3, unless the consumer adds a compile-only javax.annotation:javax.annotation-api dependency solely for the generated annotation.

The same result is produced when useSealedOneOfInterfaces is omitted or set to false.

The generated oneOf interface contains:

@javax.annotation.Generated(...)
public sealed interface Request permits NormalRequest, EmergencyRequest {
}

The generated code fails in a Jakarta-only project because javax.annotation.Generated is absent.

With useJakartaEe=true, the generated oneOf interface should contain:

@jakarta.annotation.Generated(...)
public sealed interface Request permits NormalRequest, EmergencyRequest {
}

openapi-generator version

7.24.0. Probably not a regression.

OpenAPI declaration file content or url

Minimal OpenAPI 3.0.3 document:

openapi: 3.0.3
info:
  title: oneOf Jakarta test
  version: 1.0.0
paths: {}
components:
  schemas:
    Request:
      oneOf:
        - $ref: "#/components/schemas/NormalRequest"
        - $ref: "#/components/schemas/EmergencyRequest"
    NormalRequest:
      type: object
      properties:
        kind:
          type: string
          enum: [normal]
    EmergencyRequest:
      type: object
      properties:
        kind:
          type: string
          enum: [emergency]

Generation Details

Generation options:

generatorName=java
library=microprofile
serializationLibrary=jackson
useJakartaEe=true
useOneOfInterfaces=true
useSealedOneOfInterfaces=true

Steps to reproduce

1. Save above reproducing yaml to file
2. Generate using options given above
3. Inspect @Generated statements of generated model

Related issues/PRs

• [java][microprofile] Extend useSealedOneOfInterfaces support to the microprofile library #24267 added useSealedOneOfInterfaces support for the Java MicroProfile library in 7.24.0.
• [BUG] [JAVA] generator oneOf (<useOneOfInterfaces>, <useSealedOneOfInterfaces>-> true) doesn't work during deserialization #22927 reports other discriminator-free Java oneOf interface behavior.

Suggest a fix

Ensure the shared oneOf interface generation path resolves @Generated through the generator's configured javaxPackage, as the regular Java/MicroProfile model generation path does.

Please add regression coverage for the Java microprofile library with Jackson, useJakartaEe=true, useOneOfInterfaces=true, and useSealedOneOfInterfaces=true; assert that the generated oneOf interface uses jakarta.annotation.Generated.

Workaround

Consumers can add:

compileOnly "javax.annotation:javax.annotation-api:1.3.2"

Generated has source retention, so this is a compile-time bridge only. It should not be necessary when useJakartaEe=true.

---

Note: This issue was reported with AI assistance. The reproduction and generated output were verified by the reporter.

[Mattias-Sehlstedt]

It seems Jakarta is tied to the microprofileRestClientVersion, and that 3.0 is for jakarta. See this configuration. Are you sure that you intend to run 2.0 with jakarta?

[svifred]

It seems Jakarta is tied to the microprofileRestClientVersion, and that 3.0 is for jakarta. See this configuration. Are you sure that you intend to run 2.0 with jakarta?

Ah! No, I had not noticed that. Using MicroProfile REST Client 3.0 by setting microprofileRestClientVersion=3.0 creates Jakarka annotations @jakarta.annotation.Generated.

Solved! Thanks for a quick reply :)