[Java] doesnt generate correct classes for models with same nested properties

Description

If there are two models in the swagger definition whose subproperties are the same, the code generator always uses the first one.

e.g. take the following two definitions

  house:
    type: object
    properties:
      has_walls:
        type: boolean
      attributes:
        type: object
        properties:
          name:
            type: string
  
  person:
    type: object
    properties:
      has_legs:
        type: boolean
      attributes:
        type: object
        properties:
          name:
            type: string

Swagger doesnt generate a PersonAttributes class at all, and instead generates:

public class Person   {
  @JsonProperty("has_legs")
  private Boolean hasLegs = null;

  @JsonProperty("attributes")
  private HouseAttributes attributes = null;

Swagger-codegen version

Latest snapshot 2.2.2

Swagger declaration file content or url

swagger: '2.0'
info:
  version: 0.0.0
  title: Simple API
paths:
  /:
    get:
      responses:
        200:
          description: OK
          schema:
            $ref: "#/definitions/house"
        400:
          description: OK
          schema:
            $ref: "#/definitions/person"

definitions:
  
  house:
    type: object
    properties:
      has_walls:
        type: boolean
      attributes:
        type: object
        properties:
          name:
            type: string
  
  person:
    type: object
    properties:
      has_legs:
        type: boolean
      attributes:
        type: object
        properties:
          name:
            type: string

Command line used for generation

java -jar bin/swagger-codegen-cli.jar generate -v -i ./swagger.yaml -l spring -Dmodels -o .

Steps to reproduce

Copy the above swagger.yaml into http://editor.swagger.io/#!/ or use the latest CLI to build as above.

Reproduce the issue with the supplied swagger.yaml using bin/swagger-codegen-cli.jar and the shown generate command, or the Swagger editor. Inspect the generated House and Person models and the generator entry points reached by that command. Done means distinct nested classes are generated for both models, with Person referring to PersonAttributes rather than HouseAttributes.