Spring code generation: default response rendered with 200 error code

Hi guys,

I think there's something wrong in the way the default response in paths with spring code generator is handled.

Q&A

• OS: macOS
• Browser: chrome
• Version: 72.0.3626.96
• Method of installation: npm
• Swagger-Editor version: 3.6.25
• Swagger/OpenAPI version: OpenAPI 3.0

Content & configuration

Given this definition:

openapi: 3.0.0
info:
  title: title
  description: description
  version: '0.1'
paths:
  /get:
    summary: summary
    get:
      responses:
        '200':
          description: description
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/simple'
        default:
          description: error
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/error'
components:
  schemas:
    simple:
      properties:
        myProp:
          type: string
    error:
      properties:
        errorMessage:
          type: string

and the sentence from https://github.com/OAI/OpenAPI-Specification/blob/master/versions/3.0.2.md#responseObject:

A 200 response for a successful operation and a default response for others (implying an error):

Describe the bug you're encountering

To reproduce...

Steps to reproduce the behavior:

1. Go to 'Generate server >> spring'
2. Open the generated code

Expected behavior

I would expect the default answer in case to be mapped to an error code.

Actual behavior

Hereby the generated code:

package io.swagger.api;

import io.swagger.model.Error;
import io.swagger.model.Simple;
import io.swagger.annotations.*;
import org.springframework.http.ResponseEntity;
import org.springframework.validation.annotation.Validated;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RequestHeader;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RequestPart;
import org.springframework.web.multipart.MultipartFile;

import javax.validation.Valid;
import javax.validation.constraints.*;
import java.util.List;
import java.util.Map;
@javax.annotation.Generated(value = "io.swagger.codegen.v3.generators.java.SpringCodegen", date = "2019-03-20T11:00:13.697Z[GMT]")
@Api(value = "get", description = "the get API")
public interface GetApi {

    @ApiOperation(value = "", nickname = "getGet", notes = "", response = Simple.class, tags={  })
    @ApiResponses(value = { 
        @ApiResponse(code = 200, message = "description", response = Simple.class),
        @ApiResponse(code = 200, message = "error", response = Error.class) })
    @RequestMapping(value = "/get",
        produces = { "application/json" }, 
        method = RequestMethod.GET)
    ResponseEntity<Simple> getGet();

}

As you can see, error is mapped with a 200 error code

Additional context or thoughts

Start with the generated Java GetApi example in the issue and trace the Spring generator or Mustache template that produces its @ApiResponse entries. Reproduce the OpenAPI definition with Generate server >> spring, then verify that the default response is emitted with an appropriate non-200 error code and that the generated response type remains correct.