public JSchemaWriter(JsonWriter writer, JSchemaWriterSettings settings) { ValidationUtils.ArgumentNotNull(writer, nameof(writer)); _writer = writer; _knownSchemas = new KnownSchemaCollection(); if (settings != null) { _externalSchemas = settings.ExternalSchemas; _referenceHandling = settings.ReferenceHandling; } if (_referenceHandling != JSchemaWriterReferenceHandling.Always) { _schemaStack = new List <JSchema>(); } }