cannot deserialize from Object value (Grallvm native executable)

[YunaBraska]

Using plain java graalvm native executables cause multiple issues. The parser mostly returns empty OpenAPI objects without any error. Only on one file I can receive an error. I tried to initialise swagger models at run time, but this did not help --initialize-at-run-time=io.swagger.v3.oas.models
It would be really cool to know how to use the swagger parser on plain native java.

[ERROR] Failed to parse OpenAPI file [books.yaml]: Cannot construct instance of `io.swagger.v3.oas.models.media.ArraySchema`: cannot deserialize from Object value (no delegate- or property-based Creator): this appears to be a native image, in which case you may need to configure reflection for the class that is to be deserialized
 at [Source: UNKNOWN; byte offset: #UNKNOWN]
java.lang.IllegalArgumentException: Cannot construct instance of `io.swagger.v3.oas.models.media.ArraySchema`: cannot deserialize from Object value (no delegate- or property-based Creator): this appears to be a native image, in which case you may need to configure reflection for the class that is to be deserialized
 at [Source: UNKNOWN; byte offset: #UNKNOWN]
        at com.fasterxml.jackson.databind.ObjectMapper._convert(ObjectMapper.java:4618)
        at com.fasterxml.jackson.databind.ObjectMapper.convertValue(ObjectMapper.java:4549)
        at io.swagger.v3.parser.converter.SwaggerConverter.convert(SwaggerConverter.java:1188)
        at io.swagger.v3.parser.converter.SwaggerConverter.convert(SwaggerConverter.java:865)
        at io.swagger.v3.parser.converter.SwaggerConverter.convert(SwaggerConverter.java:635)
        at io.swagger.v3.parser.converter.SwaggerConverter.convert(SwaggerConverter.java:531)
        at io.swagger.v3.parser.converter.SwaggerConverter.convert(SwaggerConverter.java:250)
        at io.swagger.v3.parser.converter.SwaggerConverter.readResult(SwaggerConverter.java:104)
        at io.swagger.v3.parser.converter.SwaggerConverter.readLocation(SwaggerConverter.java:85)
        at io.swagger.parser.OpenAPIParser.readLocation(OpenAPIParser.java:16)
        at java.base@22/java.util.stream.ReferencePipeline$3$1.accept(ReferencePipeline.java:212)
        at java.base@22/java.util.stream.ReferencePipeline$2$1.accept(ReferencePipeline.java:194)
        at java.base@22/java.util.stream.ReferencePipeline$2$1.accept(ReferencePipeline.java:194)
        at java.base@22/java.util.stream.ReferencePipeline$2$1.accept(ReferencePipeline.java:194)
        at java.base@22/java.util.stream.ReferencePipeline$2$1.accept(ReferencePipeline.java:194)
        at java.base@22/java.util.stream.ReferencePipeline$3$1.accept(ReferencePipeline.java:212)
        at java.base@22/java.util.Iterator.forEachRemaining(Iterator.java:133)
        at java.base@22/java.util.Spliterators$IteratorSpliterator.forEachRemaining(Spliterators.java:1939)
        at java.base@22/java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:556)
        at java.base@22/java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:546)
        at java.base@22/java.util.stream.ForEachOps$ForEachOp.evaluateSequential(ForEachOps.java:151)
        at java.base@22/java.util.stream.ForEachOps$ForEachOp$OfRef.evaluateSequential(ForEachOps.java:174)
        at java.base@22/java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:265)
        at java.base@22/java.util.stream.ReferencePipeline.forEach(ReferencePipeline.java:611)
Caused by: com.fasterxml.jackson.databind.exc.InvalidDefinitionException: Cannot construct instance of `io.swagger.v3.oas.models.media.ArraySchema`: cannot deserialize from Object value (no delegate- or property-based Creator): this appears to be a native image, in which case you may need to configure reflection for the class that is to be deserialized
 at [Source: UNKNOWN; byte offset: #UNKNOWN]
        at com.fasterxml.jackson.databind.DeserializationContext.reportBadDefinition(DeserializationContext.java:1887)
        at com.fasterxml.jackson.databind.DatabindContext.reportBadDefinition(DatabindContext.java:414)
        at com.fasterxml.jackson.databind.DeserializationContext.handleMissingInstantiator(DeserializationContext.java:1370)
        at com.fasterxml.jackson.databind.deser.BeanDeserializerBase.deserializeFromObjectUsingNonDefault(BeanDeserializerBase.java:1505)
        at com.fasterxml.jackson.databind.deser.BeanDeserializer.deserializeFromObject(BeanDeserializer.java:348)
        at com.fasterxml.jackson.databind.deser.BeanDeserializer.deserialize(BeanDeserializer.java:185)
        at com.fasterxml.jackson.databind.ObjectMapper._convert(ObjectMapper.java:4613)

swagger: "2.0"
info:
  version: "1.0.0"
  title: "Books API"
  description: "API to manage books, authors, and their relationships."
  termsOfService: "https://api.books.example.com/terms"
  contact:
    name: "API Support"
    url: "https://api.books.example.com/support"
    email: "support@books.example.com"
  license:
    name: "MIT"
    url: "https://opensource.org/licenses/MIT"
host: "api.books.example.com"
basePath: "/v1"
schemes:
  - https
tags:
  - name: "Books"
    description: "Operations related to books"
  - name: "Authors"
    description: "Operations related to authors"
  - name: "Management"
    description: "Administrative operations"
paths:
  /books:
    get:
      tags:
        - "Books"
      summary: "Retrieve all books"
      description: "Returns a list of all books available in the system."
      responses:
        200:
          description: "A list of books"
          schema:
            type: "array"
            items:
              $ref: "#/definitions/Book"
    post:
      tags:
        - "Books"
      summary: "Add a new book"
      description: "Adds a new book to the library."
      parameters:
        - in: "body"
          name: "body"
          required: true
          schema:
            $ref: "#/definitions/Book"
      responses:
        201:
          description: "Book created successfully"
  /books/{id}:
    get:
      tags:
        - "Books"
      summary: "Retrieve a specific book"
      description: "Fetch details of a book by its unique ID."
      parameters:
        - name: "id"
          in: "path"
          required: true
          type: "string"
      responses:
        200:
          description: "Book details retrieved"
          schema:
            $ref: "#/definitions/Book"
        404:
          description: "Book not found"
    put:
      tags:
        - "Books"
      summary: "Update a book"
      description: "Updates information for a specific book."
      parameters:
        - name: "id"
          in: "path"
          required: true
          type: "string"
        - in: "body"
          name: "body"
          required: true
          schema:
            $ref: "#/definitions/Book"
      responses:
        200:
          description: "Book updated successfully"
    delete:
      tags:
        - "Books"
      summary: "Delete a book"
      description: "Deletes a specific book by its ID."
      parameters:
        - name: "id"
          in: "path"
          required: true
          type: "string"
      responses:
        204:
          description: "Book deleted successfully"
  /authors:
    get:
      tags:
        - "Authors"
      summary: "Retrieve all authors"
      description: "Fetch a list of all authors."
      responses:
        200:
          description: "A list of authors"
          schema:
            type: "array"
            items:
              $ref: "#/definitions/Author"
    post:
      tags:
        - "Authors"
      summary: "Add a new author"
      description: "Adds a new author to the system."
      parameters:
        - in: "body"
          name: "body"
          required: true
          schema:
            $ref: "#/definitions/Author"
      responses:
        201:
          description: "Author added successfully"
definitions:
  Book:
    type: "object"
    required:
      - id
      - title
    properties:
      id:
        type: "string"
      title:
        type: "string"
      author:
        type: "string"
      publishedDate:
        type: "string"
        format: "date"
      genre:
        type: "string"
        description: "Genre of the book"
  Author:
    type: "object"
    required:
      - id
      - name
    properties:
      id:
        type: "string"
      name:
        type: "string"
      biography:
        type: "string"
        description: "A brief biography of the author"
      birthDate:
        type: "string"
        format: "date"
        description: "Author's date of birth"
securityDefinitions:
  api_key:
    type: "apiKey"
    name: "X-API-KEY"
    in: "header"
externalDocs:
  description: "Find more info here"
  url: "https://api.books.example.com/docs"

[EnricoDamini]

I have the same issue, any idea?

[YunaBraska]

@EnricoDamini
My solution was following:

1. Excluding non-necessary dependencies:
   https://github.com/YunaBraska/api-doc-crafter/blob/main/pom.xml#L76-L122

2. Created a reflection config, which is automatically taken by graalvm:
   https://github.com/YunaBraska/api-doc-crafter/blob/main/src/main/resources/META-INF/native-image/berlin.yuna/api-doc-crafter/reflect-config.json

Documentation: https://www.graalvm.org/22.2/reference-manual/native-image/guides/build-with-reflection/

The whole API-Doc-Crafter Project has just this swagger-parser as dependency and creates graalvm native executables for different platforms + docker image. Feel free to copy things.

[EnricoDamini]

I @YunaBraska

hello thanks for your help, I applied your configuration, but it seems to me that the library does not work very well with native execution.
Let me explain:

With your swagger (that you put above) I can do a correct parsing and the library correctly generates the openapi file.

However, when I try to do the same thing with this swagger the library gives me a parsing error as if the file was syntactically incorrect, but in truth it is not, in fact if I execute the same code in non-native java the library is able to parse it.

swagger: "2.0"
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 2.0"
  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"
host: "petstore.swagger.io"
basePath: "/v2"
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"
schemes:
- "https"
- "http"
paths:
  /pet:
    post:
      tags:
      - "pet"
      summary: "Add a new pet to the store"
      description: ""
      operationId: "addPet"
      consumes:
      - "application/json"
      - "application/xml"
      produces:
      - "application/xml"
      - "application/json"
      parameters:
      - in: "body"
        name: "body"
        description: "Pet object that needs to be added to the store"
        required: true
        schema:
          $ref: "#/definitions/Pet"
      responses:
        "400":
          description: Invalid input
        "422":
          description: Validation exception
      security:
      - petstore_auth:
        - "write:pets"
        - "read:pets"
    put:
      tags:
      - "pet"
      summary: "Update an existing pet"
      description: ""
      operationId: "updatePet"
      consumes:
      - "application/json"
      - "application/xml"
      produces:
      - "application/xml"
      - "application/json"
      parameters:
      - in: "body"
        name: "body"
        description: "Pet object that needs to be added to the store"
        required: true
        schema:
          $ref: "#/definitions/Pet"
      responses:
        "400":
          description: "Invalid ID supplied"
        "404":
          description: "Pet not found"
        "422":
          description: "Validation exception"
      security:
      - petstore_auth:
        - "write:pets"
        - "read:pets"
  /pet/findByStatus:
    get:
      tags:
      - "pet"
      summary: "Finds Pets by status"
      description: "Multiple status values can be provided with comma separated strings"
      operationId: "findPetsByStatus"
      produces:
      - "application/xml"
      - "application/json"
      parameters:
      - name: "status"
        in: "query"
        description: "Status values that need to be considered for filter"
        required: true
        type: "array"
        items:
          type: "string"
          enum:
          - "available"
          - "pending"
          - "sold"
          default: "available"
        collectionFormat: "multi"
      responses:
        "200":
          description: "successful operation"
          schema:
            type: "array"
            items:
              $ref: "#/definitions/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"
      produces:
      - "application/xml"
      - "application/json"
      parameters:
      - name: "tags"
        in: "query"
        description: "Tags to filter by"
        required: true
        type: "array"
        items:
          type: "string"
        collectionFormat: "multi"
      responses:
        "200":
          description: "successful operation"
          schema:
            type: "array"
            items:
              $ref: "#/definitions/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"
      produces:
      - "application/xml"
      - "application/json"
      parameters:
      - name: "petId"
        in: "path"
        description: "ID of pet to return"
        required: true
        type: "integer"
        format: "int64"
      responses:
        "200":
          description: "successful operation"
          schema:
            $ref: "#/definitions/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"
      consumes:
      - "application/x-www-form-urlencoded"
      produces:
      - "application/xml"
      - "application/json"
      parameters:
      - name: "petId"
        in: "path"
        description: "ID of pet that needs to be updated"
        required: true
        type: "integer"
        format: "int64"
      - name: "name"
        in: "formData"
        description: "Updated name of the pet"
        required: false
        type: "string"
      - name: "status"
        in: "formData"
        description: "Updated status of the pet"
        required: false
        type: "string"
      responses:
        "400":
          description: Invalid input
        "422":
          description: Validation exception
      security:
      - petstore_auth:
        - "write:pets"
        - "read:pets"
    delete:
      tags:
      - "pet"
      summary: "Deletes a pet"
      description: ""
      operationId: "deletePet"
      produces:
      - "application/xml"
      - "application/json"
      parameters:
      - name: "api_key"
        in: "header"
        required: false
        type: "string"
      - name: "petId"
        in: "path"
        description: "Pet id to delete"
        required: true
        type: "integer"
        format: "int64"
      responses:
        "400":
          description: "Invalid ID supplied"
        "404":
          description: "Pet not found"
      security:
      - petstore_auth:
        - "write:pets"
        - "read:pets"
  /pet/{petId}/uploadImage:
    post:
      tags:
      - "pet"
      summary: "uploads an image"
      description: ""
      operationId: "uploadFile"
      consumes:
      - "multipart/form-data"
      produces:
      - "application/json"
      parameters:
      - name: "petId"
        in: "path"
        description: "ID of pet to update"
        required: true
        type: "integer"
        format: "int64"
      - name: "additionalMetadata"
        in: "formData"
        description: "Additional data to pass to server"
        required: false
        type: "string"
      - name: "file"
        in: "formData"
        description: "file to upload"
        required: false
        type: "file"
      responses:
        "200":
          description: "successful operation"
          schema:
            $ref: "#/definitions/ApiResponse"
      security:
      - petstore_auth:
        - "write:pets"
        - "read:pets"
  /store/inventory:
    get:
      tags:
      - "store"
      summary: "Returns pet inventories by status"
      description: "Returns a map of status codes to quantities"
      operationId: "getInventory"
      produces:
      - "application/json"
      parameters: []
      responses:
        "200":
          description: "successful operation"
          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"
      produces:
      - "application/xml"
      - "application/json"
      parameters:
      - in: "body"
        name: "body"
        description: "order placed for purchasing the pet"
        required: true
        schema:
          $ref: "#/definitions/Order"
      responses:
        "200":
          description: "successful operation"
          schema:
            $ref: "#/definitions/Order"
        "400":
          description: "Invalid Order"
  /store/order/{orderId}:
    get:
      tags:
      - "store"
      summary: "Find purchase order by ID"
      description: "For valid response try integer IDs with value >= 1 and <= 10.         Other values will generated exceptions"
      operationId: "getOrderById"
      produces:
      - "application/xml"
      - "application/json"
      parameters:
      - name: "orderId"
        in: "path"
        description: "ID of pet that needs to be fetched"
        required: true
        type: "integer"
        maximum: 10.0
        minimum: 1.0
        format: "int64"
      responses:
        "200":
          description: "successful operation"
          schema:
            $ref: "#/definitions/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 positive integer value.         Negative or non-integer values will generate API errors"
      operationId: "deleteOrder"
      produces:
      - "application/xml"
      - "application/json"
      parameters:
      - name: "orderId"
        in: "path"
        description: "ID of the order that needs to be deleted"
        required: true
        type: "integer"
        minimum: 1.0
        format: "int64"
      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"
      produces:
      - "application/xml"
      - "application/json"
      parameters:
      - in: "body"
        name: "body"
        description: "Created user object"
        required: true
        schema:
          $ref: "#/definitions/User"
      responses:
        default:
          description: "successful operation"
  /user/createWithArray:
    post:
      tags:
      - "user"
      summary: "Creates list of users with given input array"
      description: ""
      operationId: "createUsersWithArrayInput"
      produces:
      - "application/xml"
      - "application/json"
      parameters:
      - in: "body"
        name: "body"
        description: "List of user object"
        required: true
        schema:
          type: "array"
          items:
            $ref: "#/definitions/User"
      responses:
        default:
          description: "successful operation"
  /user/createWithList:
    post:
      tags:
      - "user"
      summary: "Creates list of users with given input array"
      description: ""
      operationId: "createUsersWithListInput"
      produces:
      - "application/xml"
      - "application/json"
      parameters:
      - in: "body"
        name: "body"
        description: "List of user object"
        required: true
        schema:
          type: "array"
          items:
            $ref: "#/definitions/User"
      responses:
        default:
          description: "successful operation"
  /user/login:
    get:
      tags:
      - "user"
      summary: "Logs user into the system"
      description: ""
      operationId: "loginUser"
      produces:
      - "application/xml"
      - "application/json"
      parameters:
      - name: "username"
        in: "query"
        description: "The user name for login"
        required: true
        type: "string"
      - name: "password"
        in: "query"
        description: "The password for login in clear text"
        required: true
        type: "string"
      responses:
        "200":
          description: "successful operation"
          schema:
            type: "string"
          headers:
            X-Rate-Limit:
              type: "integer"
              format: "int32"
              description: "calls per hour allowed by the user"
            X-Expires-After:
              type: "string"
              format: "date-time"
              description: "date in UTC when token expires"
        "400":
          description: "Invalid username/password supplied"
  /user/logout:
    get:
      tags:
      - "user"
      summary: "Logs out current logged in user session"
      description: ""
      operationId: "logoutUser"
      produces:
      - "application/xml"
      - "application/json"
      parameters: []
      responses:
        default:
          description: "successful operation"
  /user/{username}:
    get:
      tags:
      - "user"
      summary: "Get user by user name"
      description: ""
      operationId: "getUserByName"
      produces:
      - "application/xml"
      - "application/json"
      parameters:
      - name: "username"
        in: "path"
        description: "The name that needs to be fetched. Use user1 for testing. "
        required: true
        type: "string"
      responses:
        "200":
          description: "successful operation"
          schema:
            $ref: "#/definitions/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"
      produces:
      - "application/xml"
      - "application/json"
      parameters:
      - name: "username"
        in: "path"
        description: "name that need to be updated"
        required: true
        type: "string"
      - in: "body"
        name: "body"
        description: "Updated user object"
        required: true
        schema:
          $ref: "#/definitions/User"
      responses:
        "400":
          description: "Invalid user supplied"
        "404":
          description: "User not found"
    delete:
      tags:
      - "user"
      summary: "Delete user"
      description: "This can only be done by the logged in user."
      operationId: "deleteUser"
      produces:
      - "application/xml"
      - "application/json"
      parameters:
      - name: "username"
        in: "path"
        description: "The name that needs to be deleted"
        required: true
        type: "string"
      responses:
        "400":
          description: "Invalid username supplied"
        "404":
          description: "User not found"
securityDefinitions:
  petstore_auth:
    type: "oauth2"
    authorizationUrl: "http://petstore.swagger.io/oauth/dialog"
    flow: "implicit"
    scopes:
      write:pets: "modify pets in your account"
      read:pets: "read your pets"
  api_key:
    type: "apiKey"
    name: "api_key"
    in: "header"
definitions:
  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"
      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"
      category:
        $ref: "#/definitions/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: "#/definitions/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"
externalDocs:
  description: "Find out more about Swagger"
  url: "http://swagger.io"

I get this parsing error:

com.fasterxml.jackson.core.JsonParseException: Unrecognized token 'swagger': was expecting (JSON String, Number, Array, Object or token 'null', 'true' or 'false')
at [Source: REDACTED (`StreamReadFeature.INCLUDE_SOURCE_IN_LOCATION` disabled); line: 1, column: 8]
       at com.fasterxml.jackson.core.JsonParser._constructError(JsonParser.java:2572)
       at com.fasterxml.jackson.core.JsonParser._constructReadException(JsonParser.java:2598)
       at com.fasterxml.jackson.core.JsonParser._constructReadException(JsonParser.java:2606)
       at com.fasterxml.jackson.core.base.ParserMinimalBase._reportError(ParserMinimalBase.java:765)
       at com.fasterxml.jackson.core.json.ReaderBasedJsonParser._reportInvalidToken(ReaderBasedJsonParser.java:3018)
       at com.fasterxml.jackson.core.json.ReaderBasedJsonParser._handleOddValue(ReaderBasedJsonParser.java:2052)
       at com.fasterxml.jackson.core.json.ReaderBasedJsonParser.nextToken(ReaderBasedJsonParser.java:780)
       at com.fasterxml.jackson.databind.ObjectMapper._readTreeAndClose(ObjectMapper.java:4934)
       at com.fasterxml.jackson.databind.ObjectMapper.readTree(ObjectMapper.java:3280)
       at io.swagger.parser.SwaggerCompatConverter.readResourceListing(SwaggerCompatConverter.java:209)
       at io.swagger.parser.SwaggerCompatConverter.read(SwaggerCompatConverter.java:122)
       at io.swagger.parser.SwaggerCompatConverter.readWithInfo(SwaggerCompatConverter.java:93)
       at io.swagger.parser.SwaggerParser.readWithInfo(SwaggerParser.java:44)
       at io.swagger.v3.parser.converter.SwaggerConverter.readLocation(SwaggerConverter.java:90)
       at io.swagger.parser.OpenAPIParser.readLocation(OpenAPIParser.java:16)

[YunaBraska]

@EnricoDamini
I feel your pain. Many libraries are not graalvm ready. I hope we can get libs with better quality in the future.

Anyway, there are few things you can do.

1. update your swagger file, swagger: "2.0" is old format, or try to add openapi: "3.0.0" on top of it.
2. if 1. did not help, try different parsers with different options, like this: Processor.