Remove lazy definition initialization in SchemaValidator

[Sven Döring]

That lazy initialization is a possible source of a false positive validation error. The method setupSchemaDefinitionRefs, which loads the definition on first validation, might throw an:

• JsonParseException leading to validation.{keyPrefix}.schema.invalidJson
• IOException leading to validation.{keyPrefix}.schema.unknownError

Both is wrong as not the tested schema is wrong but the (OpenAPI) api.

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The calculation of definitionsContainAllOf seems wrong, too. It is repeatedly set on a for-loop. So it might be set to true and on the next iteration it is set back to false again.

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Plus there are several unneccessary conversions from an Object to a JSON string back to an Object (JsonNode) instead of just converting it directly to the JsonNode.

There is potential to improve the SchemaValidator.

[Sven Döring]

And the SchemaValidator has an additional constructor which is only used for testing. But there is no (visible?) reason why those tests can’t be simply called with the other constructor.

[James Navin]

Available in v2.7.1