Question by Swagger Compliance Assertion

[hollligan]

Hello, I use Ready! API 1.9.0.
Created a new project and imported a Swagger - http://petstore.swagger.io/v2/swagger.json.

Then, I formed a Testcase with a GET request to "/v2/pet/findByStatus"
and added "Swagger Compliance Assertion" to check the JSON response according to the swagger schema.

Got error - "Could not initialize class com.github.fge.jsonschema.cfg.ValidationConfigurationBuilder".

Please tell me what I did wrong or what steps I missed.

Thank you in advance.