Fix Jspecify nullable issue with spring boot 4

[JFCote]

@cachescrubber (2022/02) @welshm (2022/02) @MelleD (2022/02) @atextor (2022/02) @manedev79 (2022/02) @javisst (2022/02) @borsch (2022/02) @banlevente (2022/02) @Zomzog (2022/09) @martin-mfg (2023/08)

Very small fix to the Spring Generator. The path parameter was the only one that did not add nullableAnnotation which did not reset the internal state.

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---

Summary by cubic

Fixes missing nullability on Spring path parameters for Spring Boot 4 by adding the nullableAnnotation. This makes JSpecify handling consistent and prevents state leakage during generation.

• Bug Fixes
  • Added {{>nullableAnnotation}} before {{>optionalDataType}} in JavaSpring/pathParams.mustache so path params reset nullability state and get the correct annotation.

^{Written for commit 8284110. Summary will update on new commits. Review in cubic}

[cubic-dev-ai]

No issues found across 1 file

[jpfinne]

@JFCote pathParams are always required in Spring.
Not sure if there was a bug.

The build succeeds. It means that no Spring sample is impacted.
Can you share your openapi api?

[raichuchuchu]

Hay I think you just solve my problem #23653

[JFCote]

@jpfinne See below for my spec but you can also check the @raichuchuchu bugs he just shared, this is exactly the issue!

#23653

Here is the openapi spec I used for my tests:

openapi: 3.0.0
info:
  title: API - Address
  version: 1.0.0
tags:
  - name: Address
    description: Address calls

paths:
  /api/addresses/{addressId}:
    put:
      summary: Updates an address by ID
      operationId: updateAddress
      tags:
        - Address
      parameters:
        - $ref: '#/components/parameters/addressId'
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/AddressCore'
      responses:
        '200':
          description: Ok
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Address'
        '404':
          description: Not Found
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Error'
    delete:
      summary: Deletes an address by ID
      operationId: deleteAddress
      tags:
        - Address
      parameters:
        - $ref: '#/components/parameters/addressId'
      responses:
        '204':
          description: No Content

components:
  parameters:
    addressId:
      name: addressId
      in: path
      required: true
      description: The ID of the address
      schema:
        type: integer
        format: int64
        example: 12345

  schemas:
    AddressCore:
      type: object
      properties:
        friendlyName:
          type: string
          example: "Headquarters"
        addressLine1:
          type: string
          example: "123 Main St"
        addressLine2:
          type: string
          example: "Suite 456"
        city:
          type: string
          example: "Sherbrooke"
        province:
          type: string
          example: "Quebec"
        postalCode:
          type: string
          example: "J1H 5N4"
        country:
          type: string
          example: "Canada"
      required:
        - friendlyName
        - addressLine1
        - city
        - province
        - postalCode
        - country

    Address:
      allOf:
        - $ref: '#/components/schemas/AddressCore'
        - type: object
          properties:
            id:
              type: integer
              format: int64
              example: 12345
            updatedAt:
              type: string
              format: date-time
              example: "2025-08-05T18:48:59.149Z"
          required:
            - id
            - updatedAt
    Error:
      type: object
      properties:
        timestamp:
          type: string
          format: date-time
          example: "2025-08-05T18:48:59.149Z"
        status:
          type: integer
          format: int32
          example: 404
        message:
          type: string
          example: "Resource not found"
        path:
          type: string
          example: "/api/addresses/12345"

And I generate with this command: java.exe -jar openapi-generator-cli.jar generate --generator-name spring --input-spec openapi.yaml --output generatedTest --api-package ca.acme.controllers --model-package ca.acme.models --model-name-suffix Model --additional-properties interfaceOnly=false,useTags=true,library=spring-boot,generateBuilders=true,generateConstructorWithAllArgs=true,hideGenerationTimestamp=true,useSwaggerUI=true,skipDefaultInterface=false,useSpringBoot4=true,useJspecify=true

Without my fix, the first method deleteAddress will have a @nullable even if the path parameter is required. The "updateAddress` will not have the @nullable. I dig very deep with the help of Codex and found that there is an object that is stateful that manage this and without my addition, the first one will always be nullable.