Generating Server Stubs for Spring results in the variables names to be changed from original snake_case to camelCase (which is wrong!)

Description

I generate a server-api from a clean YAML file, and all parameters names gets changed from snake_case to camelCase in the @RequestParam(value="") annotations that is being generated.

Swagger-codegen version

2.2.2

Swagger declaration file content or url

swagger: '2.0'
info:
  title: Bug Report
  description: |
  version: "1.0.0"

host:  localhost:8080

schemes:
  - http
  - https

securityDefinitions:
  userSecurity:
    type: apiKey
    in: header
    name: session_id

# will be prefixed to all paths
basePath: /rest/v1
consumes:
  - application/x-www-form-urlencoded
produces:
  - application/json
paths:

  /search/messages:
    get:
      operationId: "SearchMessages"
      summary: |
        Search for messages
      description: |
      consumes:
        - "*/*"
      parameters:
        - name: category_id
          in: query
          description: |
          required: true
          type: integer
          format: int64

      tags:
        - bug
      responses:
        200:
          description: |
            An array of bug
          schema:
            type: array
            items:
              $ref: '#/definitions/BugPreview'
        default:
          description: |
            Unexpected error
          schema:
            $ref: '#/definitions/ApiError'
      security:
        - userSecurity: []


definitions:


  BugPreview:
    type: object
    description: |
      Preview message object, used for list display.
    required:
      - id
    properties:
      id:
        type: integer
        format: int64


  ApiError:
    type: object
    required:
      - code
    properties:
      code:
        type: integer
        format: int32
        description: |
          Internal server error code

Command line used for generation

config.json

{
  "projectName": "BugReport",
  "classPrefix": "BugReport",
  "swiftUseApiNamespace": false,
  "sortParamsByRequiredFlag": true,
  "ensureUniqueParams": true,
  "modelPropertyNaming": "camelCase",
  "hideGenerationTimestamp": true,
  "groupId": "bug-report",
  "artifactId": "bug-report",
  "artifactVersion": "999.99-SNAPSHOT",
  "interfaceOnly" : true,
  "java8": true,
  "useAndroidMavenGradlePlugin": false,
  "dateLibrary": "java8"
}

java -jar swagger-codegen-cli-2.2.2.jar generate -i ./bug.yaml --config config.json -l spring -o ./server-api --api-package server.api --model-package server.model

Steps to reproduce

• Download the archive script.zip
• Use gen.sh
• Notice that the @RequestParam(value="") are in camelCase

Related issues

Not that I could find

Suggest a Fix

In io.swagger.codegen.languages.AbstractJavaCodegen#toParamName, should stop using io.swagger.codegen.languages.AbstractJavaCodegen#toVarName which mangles the names from whatever they were, and convert them to camelCase

Start in io.swagger.codegen.languages.AbstractJavaCodegen at toParamName and toVarName, then reproduce the Spring server generation with the supplied YAML, config.json, and command. Verify the generated @RequestParam(value="") preserves the original snake_case parameter name rather than changing it to camelCase.