diff --git a/modules/openapi-generator/src/test/resources/3_0/petstore-with-fake-endpoints-models-for-testing.yaml b/modules/openapi-generator/src/test/resources/3_0/petstore-with-fake-endpoints-models-for-testing.yaml
new file mode 100644
index 0000000000..fa3e490a4b
--- /dev/null
+++ b/modules/openapi-generator/src/test/resources/3_0/petstore-with-fake-endpoints-models-for-testing.yaml
@@ -0,0 +1,1407 @@
+openapi: 3.0.0
+servers:
+  - url: 'http://petstore.swagger.io:80/v2'
+info:
+  description: >-
+    This spec is mainly for testing Petstore server and contains fake endpoints,
+    models. Please do not use this for any other purpose. Special characters: "
+    \
+  version: 1.0.0
+  title: Swagger Petstore
+  termsOfService: 'http://swagger.io/terms/'
+  contact:
+    email: apiteam@swagger.io
+  license:
+    name: Apache-2.0
+    url: 'http://www.apache.org/licenses/LICENSE-2.0.html'
+tags:
+  - name: pet
+    description: Everything about your Pets
+    externalDocs:
+      description: Find out more
+      url: 'http://swagger.io'
+  - name: store
+    description: Access to Petstore orders
+  - name: user
+    description: Operations about user
+    externalDocs:
+      description: Find out more about our store
+      url: 'http://swagger.io'
+paths:
+  /pet:
+    post:
+      tags:
+        - pet
+      summary: Add a new pet to the store
+      description: ''
+      operationId: addPet
+      responses:
+        '405':
+          description: Invalid input
+      security:
+        - petstore_auth:
+            - 'write:pets'
+            - 'read:pets'
+      requestBody:
+        $ref: '#/components/requestBodies/Pet'
+    put:
+      tags:
+        - pet
+      summary: Update an existing pet
+      description: ''
+      operationId: updatePet
+      responses:
+        '400':
+          description: Invalid ID supplied
+        '404':
+          description: Pet not found
+        '405':
+          description: Validation exception
+      security:
+        - petstore_auth:
+            - 'write:pets'
+            - 'read:pets'
+      requestBody:
+        $ref: '#/components/requestBodies/Pet'
+  /pet/findByStatus:
+    get:
+      tags:
+        - pet
+      summary: Finds Pets by status
+      description: Multiple status values can be provided with comma separated strings
+      operationId: findPetsByStatus
+      parameters:
+        - name: status
+          in: query
+          description: Status values that need to be considered for filter
+          required: true
+          style: form
+          schema:
+            type: array
+            items:
+              type: string
+              enum:
+                - available
+                - pending
+                - sold
+              default: available
+      responses:
+        '200':
+          description: successful operation
+          content:
+            application/xml:
+              schema:
+                type: array
+                items:
+                  $ref: '#/components/schemas/Pet'
+            application/json:
+              schema:
+                type: array
+                items:
+                  $ref: '#/components/schemas/Pet'
+        '400':
+          description: Invalid status value
+      security:
+        - petstore_auth:
+            - 'write:pets'
+            - 'read:pets'
+  /pet/findByTags:
+    get:
+      tags:
+        - pet
+      summary: Finds Pets by tags
+      description: >-
+        Multiple tags can be provided with comma separated strings. Use tag1,
+        tag2, tag3 for testing.
+      operationId: findPetsByTags
+      parameters:
+        - name: tags
+          in: query
+          description: Tags to filter by
+          required: true
+          style: form
+          schema:
+            type: array
+            items:
+              type: string
+      responses:
+        '200':
+          description: successful operation
+          content:
+            application/xml:
+              schema:
+                type: array
+                items:
+                  $ref: '#/components/schemas/Pet'
+            application/json:
+              schema:
+                type: array
+                items:
+                  $ref: '#/components/schemas/Pet'
+        '400':
+          description: Invalid tag value
+      security:
+        - petstore_auth:
+            - 'write:pets'
+            - 'read:pets'
+      deprecated: true
+  '/pet/{petId}':
+    get:
+      tags:
+        - pet
+      summary: Find pet by ID
+      description: Returns a single pet
+      operationId: getPetById
+      parameters:
+        - name: petId
+          in: path
+          description: ID of pet to return
+          required: true
+          schema:
+            type: integer
+            format: int64
+      responses:
+        '200':
+          description: successful operation
+          content:
+            application/xml:
+              schema:
+                $ref: '#/components/schemas/Pet'
+            application/json:
+              schema:
+                $ref: '#/components/schemas/Pet'
+        '400':
+          description: Invalid ID supplied
+        '404':
+          description: Pet not found
+      security:
+        - api_key: []
+    post:
+      tags:
+        - pet
+      summary: Updates a pet in the store with form data
+      description: ''
+      operationId: updatePetWithForm
+      parameters:
+        - name: petId
+          in: path
+          description: ID of pet that needs to be updated
+          required: true
+          schema:
+            type: integer
+            format: int64
+      responses:
+        '405':
+          description: Invalid input
+      security:
+        - petstore_auth:
+            - 'write:pets'
+            - 'read:pets'
+      requestBody:
+        content:
+          application/x-www-form-urlencoded:
+            schema:
+              type: object
+              properties:
+                name:
+                  description: Updated name of the pet
+                  type: string
+                status:
+                  description: Updated status of the pet
+                  type: string
+    delete:
+      tags:
+        - pet
+      summary: Deletes a pet
+      description: ''
+      operationId: deletePet
+      parameters:
+        - name: api_key
+          in: header
+          required: false
+          schema:
+            type: string
+        - name: petId
+          in: path
+          description: Pet id to delete
+          required: true
+          schema:
+            type: integer
+            format: int64
+      responses:
+        '400':
+          description: Invalid pet value
+      security:
+        - petstore_auth:
+            - 'write:pets'
+            - 'read:pets'
+  '/pet/{petId}/uploadImage':
+    post:
+      tags:
+        - pet
+      summary: uploads an image
+      description: ''
+      operationId: uploadFile
+      parameters:
+        - name: petId
+          in: path
+          description: ID of pet to update
+          required: true
+          schema:
+            type: integer
+            format: int64
+      responses:
+        '200':
+          description: successful operation
+          content:
+            application/json:
+              schema:
+                $ref: '#/components/schemas/ApiResponse'
+      security:
+        - petstore_auth:
+            - 'write:pets'
+            - 'read:pets'
+      requestBody:
+        content:
+          multipart/form-data:
+            schema:
+              type: object
+              properties:
+                additionalMetadata:
+                  description: Additional data to pass to server
+                  type: string
+                file:
+                  description: file to upload
+                  type: string
+                  format: binary
+  /store/inventory:
+    get:
+      tags:
+        - store
+      summary: Returns pet inventories by status
+      description: Returns a map of status codes to quantities
+      operationId: getInventory
+      responses:
+        '200':
+          description: successful operation
+          content:
+            application/json:
+              schema:
+                type: object
+                additionalProperties:
+                  type: integer
+                  format: int32
+      security:
+        - api_key: []
+  /store/order:
+    post:
+      tags:
+        - store
+      summary: Place an order for a pet
+      description: ''
+      operationId: placeOrder
+      responses:
+        '200':
+          description: successful operation
+          content:
+            application/xml:
+              schema:
+                $ref: '#/components/schemas/Order'
+            application/json:
+              schema:
+                $ref: '#/components/schemas/Order'
+        '400':
+          description: Invalid Order
+      requestBody:
+        content:
+          application/json:
+            schema:
+              $ref: '#/components/schemas/Order'
+        description: order placed for purchasing the pet
+        required: true
+  '/store/order/{order_id}':
+    get:
+      tags:
+        - store
+      summary: Find purchase order by ID
+      description: >-
+        For valid response try integer IDs with value <= 5 or > 10. Other values
+        will generated exceptions
+      operationId: getOrderById
+      parameters:
+        - name: order_id
+          in: path
+          description: ID of pet that needs to be fetched
+          required: true
+          schema:
+            type: integer
+            format: int64
+            minimum: 1
+            maximum: 5
+      responses:
+        '200':
+          description: successful operation
+          content:
+            application/xml:
+              schema:
+                $ref: '#/components/schemas/Order'
+            application/json:
+              schema:
+                $ref: '#/components/schemas/Order'
+        '400':
+          description: Invalid ID supplied
+        '404':
+          description: Order not found
+    delete:
+      tags:
+        - store
+      summary: Delete purchase order by ID
+      description: >-
+        For valid response try integer IDs with value < 1000. Anything above
+        1000 or nonintegers will generate API errors
+      operationId: deleteOrder
+      parameters:
+        - name: order_id
+          in: path
+          description: ID of the order that needs to be deleted
+          required: true
+          schema:
+            type: string
+      responses:
+        '400':
+          description: Invalid ID supplied
+        '404':
+          description: Order not found
+  /user:
+    post:
+      tags:
+        - user
+      summary: Create user
+      description: This can only be done by the logged in user.
+      operationId: createUser
+      responses:
+        default:
+          description: successful operation
+      requestBody:
+        content:
+          application/json:
+            schema:
+              $ref: '#/components/schemas/User'
+        description: Created user object
+        required: true
+  /user/createWithArray:
+    post:
+      tags:
+        - user
+      summary: Creates list of users with given input array
+      description: ''
+      operationId: createUsersWithArrayInput
+      responses:
+        default:
+          description: successful operation
+      requestBody:
+        $ref: '#/components/requestBodies/UserArray'
+  /user/createWithList:
+    post:
+      tags:
+        - user
+      summary: Creates list of users with given input array
+      description: ''
+      operationId: createUsersWithListInput
+      responses:
+        default:
+          description: successful operation
+      requestBody:
+        $ref: '#/components/requestBodies/UserArray'
+  /user/login:
+    get:
+      tags:
+        - user
+      summary: Logs user into the system
+      description: ''
+      operationId: loginUser
+      parameters:
+        - name: username
+          in: query
+          description: The user name for login
+          required: true
+          schema:
+            type: string
+        - name: password
+          in: query
+          description: The password for login in clear text
+          required: true
+          schema:
+            type: string
+      responses:
+        '200':
+          description: successful operation
+          headers:
+            X-Rate-Limit:
+              description: calls per hour allowed by the user
+              schema:
+                type: integer
+                format: int32
+            X-Expires-After:
+              description: date in UTC when toekn expires
+              schema:
+                type: string
+                format: date-time
+          content:
+            application/xml:
+              schema:
+                type: string
+            application/json:
+              schema:
+                type: string
+        '400':
+          description: Invalid username/password supplied
+  /user/logout:
+    get:
+      tags:
+        - user
+      summary: Logs out current logged in user session
+      description: ''
+      operationId: logoutUser
+      responses:
+        default:
+          description: successful operation
+  '/user/{username}':
+    get:
+      tags:
+        - user
+      summary: Get user by user name
+      description: ''
+      operationId: getUserByName
+      parameters:
+        - name: username
+          in: path
+          description: The name that needs to be fetched. Use user1 for testing.
+          required: true
+          schema:
+            type: string
+      responses:
+        '200':
+          description: successful operation
+          content:
+            application/xml:
+              schema:
+                $ref: '#/components/schemas/User'
+            application/json:
+              schema:
+                $ref: '#/components/schemas/User'
+        '400':
+          description: Invalid username supplied
+        '404':
+          description: User not found
+    put:
+      tags:
+        - user
+      summary: Updated user
+      description: This can only be done by the logged in user.
+      operationId: updateUser
+      parameters:
+        - name: username
+          in: path
+          description: name that need to be deleted
+          required: true
+          schema:
+            type: string
+      responses:
+        '400':
+          description: Invalid user supplied
+        '404':
+          description: User not found
+      requestBody:
+        content:
+          application/json:
+            schema:
+              $ref: '#/components/schemas/User'
+        description: Updated user object
+        required: true
+    delete:
+      tags:
+        - user
+      summary: Delete user
+      description: This can only be done by the logged in user.
+      operationId: deleteUser
+      parameters:
+        - name: username
+          in: path
+          description: The name that needs to be deleted
+          required: true
+          schema:
+            type: string
+      responses:
+        '400':
+          description: Invalid username supplied
+        '404':
+          description: User not found
+  /fake_classname_test:
+    patch:
+      tags:
+        - 'fake_classname_tags 123#$%^'
+      summary: To test class name in snake case
+      description: To test class name in snake case
+      operationId: testClassname
+      responses:
+        '200':
+          description: successful operation
+          content:
+            application/json:
+              schema:
+                $ref: '#/components/schemas/Client'
+      security:
+        - api_key_query: []
+      requestBody:
+        $ref: '#/components/requestBodies/Client'
+  /fake:
+    patch:
+      tags:
+        - fake
+      summary: To test "client" model
+      description: To test "client" model
+      operationId: testClientModel
+      responses:
+        '200':
+          description: successful operation
+          content:
+            application/json:
+              schema:
+                $ref: '#/components/schemas/Client'
+      requestBody:
+        $ref: '#/components/requestBodies/Client'
+    get:
+      tags:
+        - fake
+      summary: To test enum parameters
+      description: To test enum parameters
+      operationId: testEnumParameters
+      parameters:
+        - name: enum_header_string_array
+          in: header
+          description: Header parameter enum test (string array)
+          schema:
+            type: array
+            items:
+              type: string
+              default: $
+              enum:
+                - '>'
+                - $
+        - name: enum_header_string
+          in: header
+          description: Header parameter enum test (string)
+          schema:
+            type: string
+            enum:
+              - _abc
+              - '-efg'
+              - (xyz)
+            default: '-efg'
+        - name: enum_query_string_array
+          in: query
+          description: Query parameter enum test (string array)
+          schema:
+            type: array
+            items:
+              type: string
+              default: $
+              enum:
+                - '>'
+                - $
+        - name: enum_query_string
+          in: query
+          description: Query parameter enum test (string)
+          schema:
+            type: string
+            enum:
+              - _abc
+              - '-efg'
+              - (xyz)
+            default: '-efg'
+        - name: enum_query_integer
+          in: query
+          description: Query parameter enum test (double)
+          schema:
+            type: integer
+            format: int32
+            enum:
+              - 1
+              - -2
+      responses:
+        '400':
+          description: Invalid request
+        '404':
+          description: Not found
+      requestBody:
+        content:
+          application/x-www-form-urlencoded:
+            schema:
+              type: object
+              properties:
+                enum_form_string_array:
+                  description: Form parameter enum test (string array)
+                  type: array
+                  items:
+                    type: string
+                    default: $
+                    enum:
+                      - '>'
+                      - $
+                enum_form_string:
+                  description: Form parameter enum test (string)
+                  type: string
+                  enum:
+                    - _abc
+                    - '-efg'
+                    - (xyz)
+                  default: '-efg'
+                enum_query_double:
+                  description: Query parameter enum test (double)
+                  type: number
+                  format: double
+                  enum:
+                    - 1.1
+                    - -1.2
+    post:
+      tags:
+        - fake
+      summary: |
+        Fake endpoint for testing various parameters
+        假端點
+        偽のエンドポイント
+        가짜 엔드 포인트
+      description: |
+        Fake endpoint for testing various parameters
+        假端點
+        偽のエンドポイント
+        가짜 엔드 포인트
+      operationId: testEndpointParameters
+      responses:
+        '400':
+          description: Invalid username supplied
+        '404':
+          description: User not found
+      security:
+        - http_basic_test: []
+      requestBody:
+        content:
+          application/x-www-form-urlencoded:
+            schema:
+              type: object
+              properties:
+                integer:
+                  description: None
+                  type: integer
+                  minimum: 10
+                  maximum: 100
+                int32:
+                  description: None
+                  type: integer
+                  format: int32
+                  minimum: 20
+                  maximum: 200
+                int64:
+                  description: None
+                  type: integer
+                  format: int64
+                number:
+                  description: None
+                  type: number
+                  minimum: 32.1
+                  maximum: 543.2
+                float:
+                  description: None
+                  type: number
+                  format: float
+                  maximum: 987.6
+                double:
+                  description: None
+                  type: number
+                  format: double
+                  minimum: 67.8
+                  maximum: 123.4
+                string:
+                  description: None
+                  type: string
+                  pattern: '/[a-z]/i'
+                pattern_without_delimiter:
+                  description: None
+                  type: string
+                  pattern: '^[A-Z].*'
+                byte:
+                  description: None
+                  type: string
+                  format: byte
+                binary:
+                  description: None
+                  type: string
+                  format: binary
+                date:
+                  description: None
+                  type: string
+                  format: date
+                dateTime:
+                  description: None
+                  type: string
+                  format: date-time
+                password:
+                  description: None
+                  type: string
+                  format: password
+                  minLength: 10
+                  maxLength: 64
+                callback:
+                  description: None
+                  type: string
+              required:
+                - number
+                - double
+                - pattern_without_delimiter
+                - byte
+  /fake/outer/number:
+    post:
+      tags:
+        - fake
+      description: Test serialization of outer number types
+      operationId: fakeOuterNumberSerialize
+      responses:
+        '200':
+          description: Output number
+          content:
+            '*/*':
+              schema:
+                $ref: '#/components/schemas/OuterNumber'
+      requestBody:
+        content:
+          application/json:
+            schema:
+              $ref: '#/components/schemas/OuterNumber'
+        description: Input number as post body
+  /fake/outer/string:
+    post:
+      tags:
+        - fake
+      description: Test serialization of outer string types
+      operationId: fakeOuterStringSerialize
+      responses:
+        '200':
+          description: Output string
+          content:
+            '*/*':
+              schema:
+                $ref: '#/components/schemas/OuterString'
+      requestBody:
+        content:
+          application/json:
+            schema:
+              $ref: '#/components/schemas/OuterString'
+        description: Input string as post body
+  /fake/outer/boolean:
+    post:
+      tags:
+        - fake
+      description: Test serialization of outer boolean types
+      operationId: fakeOuterBooleanSerialize
+      responses:
+        '200':
+          description: Output boolean
+          content:
+            '*/*':
+              schema:
+                $ref: '#/components/schemas/OuterBoolean'
+      requestBody:
+        content:
+          application/json:
+            schema:
+              $ref: '#/components/schemas/OuterBoolean'
+        description: Input boolean as post body
+  /fake/outer/composite:
+    post:
+      tags:
+        - fake
+      description: Test serialization of object with outer number type
+      operationId: fakeOuterCompositeSerialize
+      responses:
+        '200':
+          description: Output composite
+          content:
+            '*/*':
+              schema:
+                $ref: '#/components/schemas/OuterComposite'
+      requestBody:
+        content:
+          application/json:
+            schema:
+              $ref: '#/components/schemas/OuterComposite'
+        description: Input composite as post body
+  /fake/jsonFormData:
+    get:
+      tags:
+        - fake
+      summary: test json serialization of form data
+      description: ''
+      operationId: testJsonFormData
+      responses:
+        '200':
+          description: successful operation
+      requestBody:
+        content:
+          application/x-www-form-urlencoded:
+            schema:
+              type: object
+              properties:
+                param:
+                  description: field1
+                  type: string
+                param2:
+                  description: field2
+                  type: string
+              required:
+                - param
+                - param2
+  /fake/inline-additionalProperties:
+    post:
+      tags:
+        - fake
+      summary: test inline additionalProperties
+      description: ''
+      operationId: testInlineAdditionalProperties
+      responses:
+        '200':
+          description: successful operation
+      requestBody:
+        content:
+          application/json:
+            schema:
+              type: object
+              additionalProperties:
+                type: string
+        description: request body
+        required: true
+  /another-fake/dummy:
+    patch:
+      tags:
+        - $another-fake?
+      summary: To test special tags
+      description: To test special tags
+      operationId: test_special_tags
+      responses:
+        '200':
+          description: successful operation
+          content:
+            application/json:
+              schema:
+                $ref: '#/components/schemas/Client'
+      requestBody:
+        $ref: '#/components/requestBodies/Client'
+externalDocs:
+  description: Find out more about Swagger
+  url: 'http://swagger.io'
+components:
+  requestBodies:
+    UserArray:
+      content:
+        application/json:
+          schema:
+            type: array
+            items:
+              $ref: '#/components/schemas/User'
+      description: List of user object
+      required: true
+    Client:
+      content:
+        application/json:
+          schema:
+            $ref: '#/components/schemas/Client'
+      description: client model
+      required: true
+    Pet:
+      content:
+        application/json:
+          schema:
+            $ref: '#/components/schemas/Pet'
+        application/xml:
+          schema:
+            $ref: '#/components/schemas/Pet'
+      description: Pet object that needs to be added to the store
+      required: true
+  securitySchemes:
+    petstore_auth:
+      type: oauth2
+      flows:
+        implicit:
+          authorizationUrl: 'http://petstore.swagger.io/api/oauth/dialog'
+          scopes:
+            'write:pets': modify pets in your account
+            'read:pets': read your pets
+    api_key:
+      type: apiKey
+      name: api_key
+      in: header
+    api_key_query:
+      type: apiKey
+      name: api_key_query
+      in: query
+    http_basic_test:
+      type: http
+      scheme: basic
+  schemas:
+    Order:
+      type: object
+      properties:
+        id:
+          type: integer
+          format: int64
+        petId:
+          type: integer
+          format: int64
+        quantity:
+          type: integer
+          format: int32
+        shipDate:
+          type: string
+          format: date-time
+        status:
+          type: string
+          description: Order Status
+          enum:
+            - placed
+            - approved
+            - delivered
+        complete:
+          type: boolean
+          default: false
+      xml:
+        name: Order
+    Category:
+      type: object
+      properties:
+        id:
+          type: integer
+          format: int64
+        name:
+          type: string
+      xml:
+        name: Category
+    User:
+      type: object
+      properties:
+        id:
+          type: integer
+          format: int64
+          x-is-unique: true
+        username:
+          type: string
+        firstName:
+          type: string
+        lastName:
+          type: string
+        email:
+          type: string
+        password:
+          type: string
+        phone:
+          type: string
+        userStatus:
+          type: integer
+          format: int32
+          description: User Status
+      xml:
+        name: User
+    Tag:
+      type: object
+      properties:
+        id:
+          type: integer
+          format: int64
+        name:
+          type: string
+      xml:
+        name: Tag
+    Pet:
+      type: object
+      required:
+        - name
+        - photoUrls
+      properties:
+        id:
+          type: integer
+          format: int64
+          x-is-unique: true
+        category:
+          $ref: '#/components/schemas/Category'
+        name:
+          type: string
+          example: doggie
+        photoUrls:
+          type: array
+          xml:
+            name: photoUrl
+            wrapped: true
+          items:
+            type: string
+        tags:
+          type: array
+          xml:
+            name: tag
+            wrapped: true
+          items:
+            $ref: '#/components/schemas/Tag'
+        status:
+          type: string
+          description: pet status in the store
+          enum:
+            - available
+            - pending
+            - sold
+      xml:
+        name: Pet
+    ApiResponse:
+      type: object
+      properties:
+        code:
+          type: integer
+          format: int32
+        type:
+          type: string
+        message:
+          type: string
+    Return:
+      description: Model for testing reserved words
+      properties:
+        return:
+          type: integer
+          format: int32
+      xml:
+        name: Return
+    Name:
+      description: Model for testing model name same as property name
+      required:
+        - name
+      properties:
+        name:
+          type: integer
+          format: int32
+        snake_case:
+          readOnly: true
+          type: integer
+          format: int32
+        property:
+          type: string
+        123Number:
+          type: integer
+          readOnly: true
+      xml:
+        name: Name
+    200_response:
+      description: Model for testing model name starting with number
+      properties:
+        name:
+          type: integer
+          format: int32
+        class:
+          type: string
+      xml:
+        name: Name
+    ClassModel:
+      description: Model for testing model with "_class" property
+      properties:
+        _class:
+          type: string
+    Dog:
+      allOf:
+        - $ref: '#/components/schemas/Animal'
+        - type: object
+          properties:
+            breed:
+              type: string
+    Cat:
+      allOf:
+        - $ref: '#/components/schemas/Animal'
+        - type: object
+          properties:
+            declawed:
+              type: boolean
+    Animal:
+      type: object
+      discriminator:
+        propertyName: className
+      required:
+        - className
+      properties:
+        className:
+          type: string
+        color:
+          type: string
+          default: red
+    AnimalFarm:
+      type: array
+      items:
+        $ref: '#/components/schemas/Animal'
+    format_test:
+      type: object
+      required:
+        - number
+        - byte
+        - date
+        - password
+      properties:
+        integer:
+          type: integer
+          maximum: 100
+          minimum: 10
+        int32:
+          type: integer
+          format: int32
+          maximum: 200
+          minimum: 20
+        int64:
+          type: integer
+          format: int64
+        number:
+          maximum: 543.2
+          minimum: 32.1
+          type: number
+        float:
+          type: number
+          format: float
+          maximum: 987.6
+          minimum: 54.3
+        double:
+          type: number
+          format: double
+          maximum: 123.4
+          minimum: 67.8
+        string:
+          type: string
+          pattern: '/[a-z]/i'
+        byte:
+          type: string
+          format: byte
+        binary:
+          type: string
+          format: binary
+        date:
+          type: string
+          format: date
+        dateTime:
+          type: string
+          format: date-time
+        uuid:
+          type: string
+          format: uuid
+        password:
+          type: string
+          format: password
+          maxLength: 64
+          minLength: 10
+    EnumClass:
+      type: string
+      default: '-efg'
+      enum:
+        - _abc
+        - '-efg'
+        - (xyz)
+    Enum_Test:
+      type: object
+      required:
+        - enum_string_required
+      properties:
+        enum_string:
+          type: string
+          enum:
+            - UPPER
+            - lower
+            - ''
+        enum_string_required:
+          type: string
+          enum:
+            - UPPER
+            - lower
+            - ''
+        enum_integer:
+          type: integer
+          format: int32
+          enum:
+            - 1
+            - -1
+        enum_number:
+          type: number
+          format: double
+          enum:
+            - 1.1
+            - -1.2
+        outerEnum:
+          $ref: '#/components/schemas/OuterEnum'
+    AdditionalPropertiesClass:
+      type: object
+      properties:
+        map_property:
+          type: object
+          additionalProperties:
+            type: string
+        map_of_map_property:
+          type: object
+          additionalProperties:
+            type: object
+            additionalProperties:
+              type: string
+    MixedPropertiesAndAdditionalPropertiesClass:
+      type: object
+      properties:
+        uuid:
+          type: string
+          format: uuid
+        dateTime:
+          type: string
+          format: date-time
+        map:
+          type: object
+          additionalProperties:
+            $ref: '#/components/schemas/Animal'
+    List:
+      type: object
+      properties:
+        123-list:
+          type: string
+    Client:
+      type: object
+      properties:
+        client:
+          type: string
+    ReadOnlyFirst:
+      type: object
+      properties:
+        bar:
+          type: string
+          readOnly: true
+        baz:
+          type: string
+    hasOnlyReadOnly:
+      type: object
+      properties:
+        bar:
+          type: string
+          readOnly: true
+        foo:
+          type: string
+          readOnly: true
+    Capitalization:
+      type: object
+      properties:
+        smallCamel:
+          type: string
+        CapitalCamel:
+          type: string
+        small_Snake:
+          type: string
+        Capital_Snake:
+          type: string
+        SCA_ETH_Flow_Points:
+          type: string
+        ATT_NAME:
+          description: |
+            Name of the pet
+          type: string
+    MapTest:
+      type: object
+      properties:
+        map_map_of_string:
+          type: object
+          additionalProperties:
+            type: object
+            additionalProperties:
+              type: string
+        map_of_enum_string:
+          type: object
+          additionalProperties:
+            type: string
+            enum:
+              - UPPER
+              - lower
+    ArrayTest:
+      type: object
+      properties:
+        array_of_string:
+          type: array
+          items:
+            type: string
+        array_array_of_integer:
+          type: array
+          items:
+            type: array
+            items:
+              type: integer
+              format: int64
+        array_array_of_model:
+          type: array
+          items:
+            type: array
+            items:
+              $ref: '#/components/schemas/ReadOnlyFirst'
+    NumberOnly:
+      type: object
+      properties:
+        JustNumber:
+          type: number
+    ArrayOfNumberOnly:
+      type: object
+      properties:
+        ArrayNumber:
+          type: array
+          items:
+            type: number
+    ArrayOfArrayOfNumberOnly:
+      type: object
+      properties:
+        ArrayArrayNumber:
+          type: array
+          items:
+            type: array
+            items:
+              type: number
+    EnumArrays:
+      type: object
+      properties:
+        just_symbol:
+          type: string
+          enum:
+            - '>='
+            - $
+        array_enum:
+          type: array
+          items:
+            type: string
+            enum:
+              - fish
+              - crab
+    OuterEnum:
+      type: string
+      enum:
+        - placed
+        - approved
+        - delivered
+    OuterComposite:
+      type: object
+      properties:
+        my_number:
+          $ref: '#/components/schemas/OuterNumber'
+        my_string:
+          $ref: '#/components/schemas/OuterString'
+        my_boolean:
+          $ref: '#/components/schemas/OuterBoolean'
+    OuterNumber:
+      type: number
+    OuterString:
+      type: string
+    OuterBoolean:
+      type: boolean
+    _special_model.name_:
+      properties:
+        '$special[property.name]':
+          type: integer
+          format: int64
+      xml:
+        name: '$special[model.name]'
diff --git a/modules/openapi-generator/src/test/resources/3_0/petstore.yaml b/modules/openapi-generator/src/test/resources/3_0/petstore.yaml
new file mode 100644
index 0000000000..d35dcf4936
--- /dev/null
+++ b/modules/openapi-generator/src/test/resources/3_0/petstore.yaml
@@ -0,0 +1,708 @@
+openapi: 3.0.0
+servers:
+  - url: 'http://petstore.swagger.io/v2'
+info:
+  description: >-
+    This is a sample server Petstore server.  You can find out more about
+    Swagger at [http://swagger.io](http://swagger.io) or on [irc.freenode.net,
+    #swagger](http://swagger.io/irc/).  For this sample, you can use the api key
+    `special-key` to test the authorization filters.
+  version: 1.0.0
+  title: Swagger Petstore
+  termsOfService: 'http://swagger.io/terms/'
+  contact:
+    email: apiteam@swagger.io
+  license:
+    name: Apache-2.0
+    url: 'http://www.apache.org/licenses/LICENSE-2.0.html'
+tags:
+  - name: pet
+    description: Everything about your Pets
+    externalDocs:
+      description: Find out more
+      url: 'http://swagger.io'
+  - name: store
+    description: Access to Petstore orders
+  - name: user
+    description: Operations about user
+    externalDocs:
+      description: Find out more about our store
+      url: 'http://swagger.io'
+paths:
+  /pet:
+    post:
+      tags:
+        - pet
+      summary: Add a new pet to the store
+      description: ''
+      operationId: addPet
+      responses:
+        '405':
+          description: Invalid input
+      security:
+        - petstore_auth:
+            - 'write:pets'
+            - 'read:pets'
+      requestBody:
+        $ref: '#/components/requestBodies/Pet'
+    put:
+      tags:
+        - pet
+      summary: Update an existing pet
+      description: ''
+      operationId: updatePet
+      responses:
+        '400':
+          description: Invalid ID supplied
+        '404':
+          description: Pet not found
+        '405':
+          description: Validation exception
+      security:
+        - petstore_auth:
+            - 'write:pets'
+            - 'read:pets'
+      requestBody:
+        $ref: '#/components/requestBodies/Pet'
+  /pet/findByStatus:
+    get:
+      tags:
+        - pet
+      summary: Finds Pets by status
+      description: Multiple status values can be provided with comma separated strings
+      operationId: findPetsByStatus
+      parameters:
+        - name: status
+          in: query
+          description: Status values that need to be considered for filter
+          required: true
+          style: form
+          schema:
+            type: array
+            items:
+              type: string
+              enum:
+                - available
+                - pending
+                - sold
+              default: available
+      responses:
+        '200':
+          description: successful operation
+          content:
+            application/xml:
+              schema:
+                type: array
+                items:
+                  $ref: '#/components/schemas/Pet'
+            application/json:
+              schema:
+                type: array
+                items:
+                  $ref: '#/components/schemas/Pet'
+        '400':
+          description: Invalid status value
+      security:
+        - petstore_auth:
+            - 'write:pets'
+            - 'read:pets'
+  /pet/findByTags:
+    get:
+      tags:
+        - pet
+      summary: Finds Pets by tags
+      description: >-
+        Multiple tags can be provided with comma separated strings. Use tag1,
+        tag2, tag3 for testing.
+      operationId: findPetsByTags
+      parameters:
+        - name: tags
+          in: query
+          description: Tags to filter by
+          required: true
+          style: form
+          schema:
+            type: array
+            items:
+              type: string
+      responses:
+        '200':
+          description: successful operation
+          content:
+            application/xml:
+              schema:
+                type: array
+                items:
+                  $ref: '#/components/schemas/Pet'
+            application/json:
+              schema:
+                type: array
+                items:
+                  $ref: '#/components/schemas/Pet'
+        '400':
+          description: Invalid tag value
+      security:
+        - petstore_auth:
+            - 'write:pets'
+            - 'read:pets'
+      deprecated: true
+  '/pet/{petId}':
+    get:
+      tags:
+        - pet
+      summary: Find pet by ID
+      description: Returns a single pet
+      operationId: getPetById
+      parameters:
+        - name: petId
+          in: path
+          description: ID of pet to return
+          required: true
+          schema:
+            type: integer
+            format: int64
+      responses:
+        '200':
+          description: successful operation
+          content:
+            application/xml:
+              schema:
+                $ref: '#/components/schemas/Pet'
+            application/json:
+              schema:
+                $ref: '#/components/schemas/Pet'
+        '400':
+          description: Invalid ID supplied
+        '404':
+          description: Pet not found
+      security:
+        - api_key: []
+    post:
+      tags:
+        - pet
+      summary: Updates a pet in the store with form data
+      description: ''
+      operationId: updatePetWithForm
+      parameters:
+        - name: petId
+          in: path
+          description: ID of pet that needs to be updated
+          required: true
+          schema:
+            type: integer
+            format: int64
+      responses:
+        '405':
+          description: Invalid input
+      security:
+        - petstore_auth:
+            - 'write:pets'
+            - 'read:pets'
+      requestBody:
+        content:
+          application/x-www-form-urlencoded:
+            schema:
+              type: object
+              properties:
+                name:
+                  description: Updated name of the pet
+                  type: string
+                status:
+                  description: Updated status of the pet
+                  type: string
+    delete:
+      tags:
+        - pet
+      summary: Deletes a pet
+      description: ''
+      operationId: deletePet
+      parameters:
+        - name: api_key
+          in: header
+          required: false
+          schema:
+            type: string
+        - name: petId
+          in: path
+          description: Pet id to delete
+          required: true
+          schema:
+            type: integer
+            format: int64
+      responses:
+        '400':
+          description: Invalid pet value
+      security:
+        - petstore_auth:
+            - 'write:pets'
+            - 'read:pets'
+  '/pet/{petId}/uploadImage':
+    post:
+      tags:
+        - pet
+      summary: uploads an image
+      description: ''
+      operationId: uploadFile
+      parameters:
+        - name: petId
+          in: path
+          description: ID of pet to update
+          required: true
+          schema:
+            type: integer
+            format: int64
+      responses:
+        '200':
+          description: successful operation
+          content:
+            application/json:
+              schema:
+                $ref: '#/components/schemas/ApiResponse'
+      security:
+        - petstore_auth:
+            - 'write:pets'
+            - 'read:pets'
+      requestBody:
+        content:
+          multipart/form-data:
+            schema:
+              type: object
+              properties:
+                additionalMetadata:
+                  description: Additional data to pass to server
+                  type: string
+                file:
+                  description: file to upload
+                  type: string
+                  format: binary
+  /store/inventory:
+    get:
+      tags:
+        - store
+      summary: Returns pet inventories by status
+      description: Returns a map of status codes to quantities
+      operationId: getInventory
+      responses:
+        '200':
+          description: successful operation
+          content:
+            application/json:
+              schema:
+                type: object
+                additionalProperties:
+                  type: integer
+                  format: int32
+      security:
+        - api_key: []
+  /store/order:
+    post:
+      tags:
+        - store
+      summary: Place an order for a pet
+      description: ''
+      operationId: placeOrder
+      responses:
+        '200':
+          description: successful operation
+          content:
+            application/xml:
+              schema:
+                $ref: '#/components/schemas/Order'
+            application/json:
+              schema:
+                $ref: '#/components/schemas/Order'
+        '400':
+          description: Invalid Order
+      requestBody:
+        content:
+          application/json:
+            schema:
+              $ref: '#/components/schemas/Order'
+        description: order placed for purchasing the pet
+        required: true
+  '/store/order/{orderId}':
+    get:
+      tags:
+        - store
+      summary: Find purchase order by ID
+      description: >-
+        For valid response try integer IDs with value <= 5 or > 10. Other values
+        will generated exceptions
+      operationId: getOrderById
+      parameters:
+        - name: orderId
+          in: path
+          description: ID of pet that needs to be fetched
+          required: true
+          schema:
+            type: integer
+            format: int64
+            minimum: 1
+            maximum: 5
+      responses:
+        '200':
+          description: successful operation
+          content:
+            application/xml:
+              schema:
+                $ref: '#/components/schemas/Order'
+            application/json:
+              schema:
+                $ref: '#/components/schemas/Order'
+        '400':
+          description: Invalid ID supplied
+        '404':
+          description: Order not found
+    delete:
+      tags:
+        - store
+      summary: Delete purchase order by ID
+      description: >-
+        For valid response try integer IDs with value < 1000. Anything above
+        1000 or nonintegers will generate API errors
+      operationId: deleteOrder
+      parameters:
+        - name: orderId
+          in: path
+          description: ID of the order that needs to be deleted
+          required: true
+          schema:
+            type: string
+      responses:
+        '400':
+          description: Invalid ID supplied
+        '404':
+          description: Order not found
+  /user:
+    post:
+      tags:
+        - user
+      summary: Create user
+      description: This can only be done by the logged in user.
+      operationId: createUser
+      responses:
+        default:
+          description: successful operation
+      requestBody:
+        content:
+          application/json:
+            schema:
+              $ref: '#/components/schemas/User'
+        description: Created user object
+        required: true
+  /user/createWithArray:
+    post:
+      tags:
+        - user
+      summary: Creates list of users with given input array
+      description: ''
+      operationId: createUsersWithArrayInput
+      responses:
+        default:
+          description: successful operation
+      requestBody:
+        $ref: '#/components/requestBodies/UserArray'
+  /user/createWithList:
+    post:
+      tags:
+        - user
+      summary: Creates list of users with given input array
+      description: ''
+      operationId: createUsersWithListInput
+      responses:
+        default:
+          description: successful operation
+      requestBody:
+        $ref: '#/components/requestBodies/UserArray'
+  /user/login:
+    get:
+      tags:
+        - user
+      summary: Logs user into the system
+      description: ''
+      operationId: loginUser
+      parameters:
+        - name: username
+          in: query
+          description: The user name for login
+          required: true
+          schema:
+            type: string
+        - name: password
+          in: query
+          description: The password for login in clear text
+          required: true
+          schema:
+            type: string
+      responses:
+        '200':
+          description: successful operation
+          headers:
+            X-Rate-Limit:
+              description: calls per hour allowed by the user
+              schema:
+                type: integer
+                format: int32
+            X-Expires-After:
+              description: date in UTC when toekn expires
+              schema:
+                type: string
+                format: date-time
+          content:
+            application/xml:
+              schema:
+                type: string
+            application/json:
+              schema:
+                type: string
+        '400':
+          description: Invalid username/password supplied
+  /user/logout:
+    get:
+      tags:
+        - user
+      summary: Logs out current logged in user session
+      description: ''
+      operationId: logoutUser
+      responses:
+        default:
+          description: successful operation
+  '/user/{username}':
+    get:
+      tags:
+        - user
+      summary: Get user by user name
+      description: ''
+      operationId: getUserByName
+      parameters:
+        - name: username
+          in: path
+          description: The name that needs to be fetched. Use user1 for testing.
+          required: true
+          schema:
+            type: string
+      responses:
+        '200':
+          description: successful operation
+          content:
+            application/xml:
+              schema:
+                $ref: '#/components/schemas/User'
+            application/json:
+              schema:
+                $ref: '#/components/schemas/User'
+        '400':
+          description: Invalid username supplied
+        '404':
+          description: User not found
+    put:
+      tags:
+        - user
+      summary: Updated user
+      description: This can only be done by the logged in user.
+      operationId: updateUser
+      parameters:
+        - name: username
+          in: path
+          description: name that need to be deleted
+          required: true
+          schema:
+            type: string
+      responses:
+        '400':
+          description: Invalid user supplied
+        '404':
+          description: User not found
+      requestBody:
+        content:
+          application/json:
+            schema:
+              $ref: '#/components/schemas/User'
+        description: Updated user object
+        required: true
+    delete:
+      tags:
+        - user
+      summary: Delete user
+      description: This can only be done by the logged in user.
+      operationId: deleteUser
+      parameters:
+        - name: username
+          in: path
+          description: The name that needs to be deleted
+          required: true
+          schema:
+            type: string
+      responses:
+        '400':
+          description: Invalid username supplied
+        '404':
+          description: User not found
+externalDocs:
+  description: Find out more about Swagger
+  url: 'http://swagger.io'
+components:
+  requestBodies:
+    UserArray:
+      content:
+        application/json:
+          schema:
+            type: array
+            items:
+              $ref: '#/components/schemas/User'
+      description: List of user object
+      required: true
+    Pet:
+      content:
+        application/json:
+          schema:
+            $ref: '#/components/schemas/Pet'
+        application/xml:
+          schema:
+            $ref: '#/components/schemas/Pet'
+      description: Pet object that needs to be added to the store
+      required: true
+  securitySchemes:
+    petstore_auth:
+      type: oauth2
+      flows:
+        implicit:
+          authorizationUrl: 'http://petstore.swagger.io/api/oauth/dialog'
+          scopes:
+            'write:pets': modify pets in your account
+            'read:pets': read your pets
+    api_key:
+      type: apiKey
+      name: api_key
+      in: header
+  schemas:
+    Order:
+      title: Pet Order
+      description: An order for a pets from the pet store
+      type: object
+      properties:
+        id:
+          type: integer
+          format: int64
+        petId:
+          type: integer
+          format: int64
+        quantity:
+          type: integer
+          format: int32
+        shipDate:
+          type: string
+          format: date-time
+        status:
+          type: string
+          description: Order Status
+          enum:
+            - placed
+            - approved
+            - delivered
+        complete:
+          type: boolean
+          default: false
+      xml:
+        name: Order
+    Category:
+      title: Pet category
+      description: A category for a pet
+      type: object
+      properties:
+        id:
+          type: integer
+          format: int64
+        name:
+          type: string
+      xml:
+        name: Category
+    User:
+      title: a User
+      description: A User who is purchasing from the pet store
+      type: object
+      properties:
+        id:
+          type: integer
+          format: int64
+        username:
+          type: string
+        firstName:
+          type: string
+        lastName:
+          type: string
+        email:
+          type: string
+        password:
+          type: string
+        phone:
+          type: string
+        userStatus:
+          type: integer
+          format: int32
+          description: User Status
+      xml:
+        name: User
+    Tag:
+      title: Pet Tag
+      description: A tag for a pet
+      type: object
+      properties:
+        id:
+          type: integer
+          format: int64
+        name:
+          type: string
+      xml:
+        name: Tag
+    Pet:
+      title: a Pet
+      description: A pet for sale in the pet store
+      type: object
+      required:
+        - name
+        - photoUrls
+      properties:
+        id:
+          type: integer
+          format: int64
+        category:
+          $ref: '#/components/schemas/Category'
+        name:
+          type: string
+          example: doggie
+        photoUrls:
+          type: array
+          xml:
+            name: photoUrl
+            wrapped: true
+          items:
+            type: string
+        tags:
+          type: array
+          xml:
+            name: tag
+            wrapped: true
+          items:
+            $ref: '#/components/schemas/Tag'
+        status:
+          type: string
+          description: pet status in the store
+          enum:
+            - available
+            - pending
+            - sold
+      xml:
+        name: Pet
+    ApiResponse:
+      title: An uploaded response
+      description: Describes the result of uploading an image resource
+      type: object
+      properties:
+        code:
+          type: integer
+          format: int32
+        type:
+          type: string
+        message:
+          type: string