Swagger-codegen generated method expects structured JSON response, while actual HTTP response from server is an XML document

Hello!

I am using swagger-codegen-maven-plugin to generate a Java REST API client to use a REST API.
However, the swagger-codegen generated method expects structured JSON response, while the actual HTTP response from server is an XML document file containing an invoice.

The REST API has a method to get an invoice, as documented here:
https://swagger.maventa.com/#/invoices/getV1InvoicesId

The problem is that this API endpoint actually returns an XML file, which I want to download, and it doesn't return the JSON response as described in the swagger definition file.

So the auto-generated Java client code would look like this:

How can I make a HTTP GET request to /v1​/invoices​/{id} using the Java generated code, and make a call to invoicesApi.getV1InvoicesId(...) and get the returned XML document in return, even though the autogenerated client expects a object InvoicesHttpApiEntitiesInvoice in the response?

Start by comparing the Swagger definition for GET /v1/invoices/{id} with the actual XML response and the generated invoicesApi.getV1InvoicesId(...) method. No repository file or test is named; the issue is resolved when the expected response format and the generated Java client's handling of the invoice document are clearly aligned.