[Java][Spring] Different in-parameter types generated for api and delegate for binary (application/octet-stream)

[EmhyrVarEmreis]

Related to #8659

Actual api endpoint is using org.springframework.core.io.Resource but delegatee is using org.springframework.web.multipart.MultipartFile
Now both are using the second one, which is recommended by Spring (according to my latest knowledge)
Tests are passing and also generation of the following endpoint works (it does not work on plain 5.1.0)

post:
  operationId: setClientFile
  tags:
    - clients
  parameters:
    - $ref: '#/components/parameters/clientId'
  requestBody:
    required: true
    content:
      application/octet-stream:
        schema:
          type: string
          format: binary
  responses:
    204:
      description: No records found
    415:
      description: Invalid image type
    200:
      description: Upload successful

@bbdouglas @sreeshas @jfiala @lukoyanov @cbornet @jeff9finger @karismann @Zomzog @lwlee2608 @nmuesch

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[EmhyrVarEmreis]

@agilob
@wing328

[xross-criss]

I am waiting for this merge too. Hope you would do it quite fast :). Thanks in advance.

[wing328]

Tested locally and the result is good.

[apinske]

That'a a breaking change in a fix-version. I have to change my code from Resource to MultipartFile and then it doesn't even work anymore because application/octet-stream is not considered by spring's multipart resolver. So the parameter is null at run time.

[beckerjohannes]

That'a a breaking change in a fix-version. I have to change my code from Resource to MultipartFile and then it doesn't even work anymore because application/octet-stream is not considered by spring's multipart resolver. So the parameter is null at run time.

Even more, it breaks the ability to return binary content. See #9462