[java][microprofile] Emit List<File> to upload multiple files when declaring an array of binary forms

[Ignacio-Vidal]

A type: array of format: binary form properties was collapsed onto the scalar File type, so a multi-file upload was generated with the same signature as a single-file one — only the array dimension was silently dropped, and only one file could ever be sent.

Given:

files:
  type: array
  items:
    type: string
    format: binary

Before (identical to the single-file signature):

void uploadMultiple(@FormParam("files") File filesDetail, @FormParam("description") String description);

After:

void uploadMultiple(@FormParam("files") List<File> filesDetail, @FormParam("description") String description);

A single binary property is still bound to a scalar File, so existing specs are unaffected — the petstore samples are byte-identical to master.

isArray was already populated on file parameters, so this is a template-only change (formParams.mustache and formParamsImpl.mustache);

This is the client-side counterpart of #24455, which fixes the same limitation in jaxrs-spec. The two are independent and can be merged in either order.

Testing

• 1 new test in JavaClientCodegenTest (testMicroprofileFormMultipartArray), reusing the existing 3_0/form-multipart-binary-array.yaml fixture and following the same shape as the neighbouring testRestTemplateFormMultipart/testWebClientFormMultipart tests.

PR checklist

• Read the contribution guidelines.
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  ./mvnw clean package || exit
  ./bin/generate-samples.sh ./bin/configs/*.yaml || exit
  ./bin/utils/export_docs_generators.sh || exit
  

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  Commit all changed files.
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---

Summary by cubic

Fixes multi-file uploads in the Java MicroProfile client by preserving the array dimension for binary form fields. Multi-file params now generate as List<File>; single-file stays File.

• Bug Fixes
  • Generate @FormParam("...") List<File> paramDetail for type: array + format: binary; scalar stays File.
  • Updated templates: formParams.mustache, formParamsImpl.mustache; no DefaultCodegen changes.
  • Added testMicroprofileFormMultipartArray using 3_0/form-multipart-binary-array.yaml; all tests pass.

^{Written for commit ec060f6. Summary will update on new commits.}

[cubic-dev-ai]

No issues found across 3 files

_{Re-trigger cubic}

[cubic-dev-ai]

No issues found across 3 files

_{Re-trigger cubic}

[Ignacio-Vidal]

@wing328 - any chance you could review?

[wing328]

lgtm. thanks for the fix