[java][spring] Add @RequestParam for oneOf/allOf-wrapped model query params

[cmagowan]

Fix #25210

Problem

When a query parameter's schema wraps a $ref to a named model in oneOf or allOf, e.g.

- name: MaxPrice
  in: query
  schema:
    nullable: true
    oneOf:
      - $ref: '#/components/schemas/Price'

the spring generator leaves out @RequestParam on the generated parameter. The parameter resolves to isModel=true, and JavaSpring/queryParams.mustache only emits @RequestParam inside a {{^isModel}} guard. That guard was added in #2710 (for #2655) so that inline object query params are bound as a model attribute. It also catches these wrapped model refs.

Fix

Keep the existing {{^isModel}} branch and add an identical @RequestParam branch for models without vars:

{{#isModel}}{{^hasVars}} @RequestParam(...){{/hasVars}}{{/isModel}}{{^isModel}} @RequestParam(...){{/isModel}}

Behaviour by query param schema (all isModel=true):

Query param schema	hasVars	Before	After
oneOf: [$ref: Price]	false	no @RequestParam	@RequestParam
allOf: [$ref: Price]	false	no @RequestParam	@RequestParam
direct $ref: Price	true	no @RequestParam	unchanged
inline type: object (#2655)	true	no @RequestParam	unchanged

Before:

@Parameter(name = "MaxPrice", description = "A model-typed query param via oneOf ref", in = ParameterIn.QUERY) @Valid Price maxPrice

After:

@Parameter(name = "MaxPrice", description = "A model-typed query param via oneOf ref", in = ParameterIn.QUERY) @Valid @RequestParam(value = "MaxPrice", required = false) Price maxPrice

Tests

• Added SpringCodegenTest#shouldGenerateRequestParamForOneOfRefQueryParam with the spec 3_0/spring/issue-model-query-param-requestparam.yaml.
• The existing tests doNotGenerateRequestParamForObjectQueryParam ([BUG] Query Parameter Serialization (Spring) #2655) and doGenerateRequestParamForSimpleParam still pass.
• Regenerated the spring* and java-camel* samples: no changes, since no sample uses a oneOf/allOf-wrapped model query param.

kotlin-spring/queryParams.mustache has the same {{^isModel}} guard but is not changed in this PR.

PR checklist

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---

Summary by cubic

Fixes @RequestParam being dropped from query parameters whose schema wraps a model $ref inside oneOf or allOf (e.g. oneOf: [$ref: Price]), which prevented Spring from binding them.

• Adds @RequestParam for model query params without variables; inline object params and direct $ref params keep their existing behavior.
• Adds a regression test covering oneOf- and allOf-wrapped model query params, plus negative cases for direct $ref and inline object params.

^{Written for commit d02ff07. Summary will update on new commits.}

[cubic-dev-ai]

1 issue found across 3 files

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Check if these issues are valid — if so, understand the root cause of each and fix them. When an issue isn't valid or won't be fixed in this PR, reply in its thread with the reason and then resolve the thread. If appropriate, use sub-agents to investigate and fix each issue separately.


<file name="modules/openapi-generator/src/main/resources/JavaSpring/queryParams.mustache">

<violation number="1" location="modules/openapi-generator/src/main/resources/JavaSpring/queryParams.mustache:1">
P1: `hasVars` is never populated for query parameters, so this branch also adds `@RequestParam` to ordinary model `$ref`s and changes their existing binding behavior. Gate this annotation on the wrapped `oneOf`/`allOf` case instead.</violation>
</file>

<sub>Reply to a comment to ask cubic a question or push back. It learns from your replies.

View guided diff | Re-trigger cubic</sub>

[cubic-dev-ai]

P1: hasVars is never populated for query parameters, so this branch also adds @RequestParam to ordinary model $refs and changes their existing binding behavior. Gate this annotation on the wrapped oneOf/allOf case instead.

Prompt for AI agents

Check if this issue is valid — if so, understand the root cause and fix it. When an issue isn't valid or won't be fixed in this PR, reply in its thread with the reason and then resolve the thread. At modules/openapi-generator/src/main/resources/JavaSpring/queryParams.mustache, line 1:

<comment>`hasVars` is never populated for query parameters, so this branch also adds `@RequestParam` to ordinary model `$ref`s and changes their existing binding behavior. Gate this annotation on the wrapped `oneOf`/`allOf` case instead.</comment>

<file context>
@@ -1 +1 @@
-{{#isQueryParam}}{{#vendorExtensions.x-field-extra-annotation}}{{{.}}} {{/vendorExtensions.x-field-extra-annotation}}{{#useBeanValidation}}{{>beanValidationQueryParams}}{{/useBeanValidation}}{{>paramDoc}}{{#useBeanValidation}}{{^isContainer}}{{#isModel}} @Valid{{/isModel}}{{^isModel}}{{^useOptional}} @Valid{{/useOptional}}{{#useOptional}}{{#required}} @Valid{{/required}}{{/useOptional}}{{/isModel}}{{/isContainer}}{{/useBeanValidation}}{{^isModel}} @RequestParam(value = {{#isMap}}""{{/isMap}}{{^isMap}}"{{baseName}}"{{/isMap}}{{#required}}, required = true{{/required}}{{^required}}, required = false{{/required}}{{#defaultValue}}, defaultValue = "{{{.}}}"{{/defaultValue}}){{/isModel}}{{>dateTimeParam}}{{#isDeprecated}} @Deprecated{{/isDeprecated}} {{>nullableAnnotation}}{{>optionalDataType}} {{paramName}}{{/isQueryParam}}
\ No newline at end of file
+{{#isQueryParam}}{{#vendorExtensions.x-field-extra-annotation}}{{{.}}} {{/vendorExtensions.x-field-extra-annotation}}{{#useBeanValidation}}{{>beanValidationQueryParams}}{{/useBeanValidation}}{{>paramDoc}}{{#useBeanValidation}}{{^isContainer}}{{#isModel}} @Valid{{/isModel}}{{^isModel}}{{^useOptional}} @Valid{{/useOptional}}{{#useOptional}}{{#required}} @Valid{{/required}}{{/useOptional}}{{/isModel}}{{/isContainer}}{{/useBeanValidation}}{{#isModel}}{{^hasVars}} @RequestParam(value = {{#isMap}}""{{/isMap}}{{^isMap}}"{{baseName}}"{{/isMap}}{{#required}}, required = true{{/required}}{{^required}}, required = false{{/required}}{{#defaultValue}}, defaultValue = "{{{.}}}"{{/defaultValue}}){{/hasVars}}{{/isModel}}{{^isModel}} @RequestParam(value = {{#isMap}}""{{/isMap}}{{^isMap}}"{{baseName}}"{{/isMap}}{{#required}}, required = true{{/required}}{{^required}}, required = false{{/required}}{{#defaultValue}}, defaultValue = "{{{.}}}"{{/defaultValue}}){{/isModel}}{{>dateTimeParam}}{{#isDeprecated}} @Deprecated{{/isDeprecated}} {{>nullableAnnotation}}{{>optionalDataType}} {{paramName}}{{/isQueryParam}}
\ No newline at end of file
</file context>