private static Object convert(JsonNode value) {
        if (value.isArray()) {
            List<String> retvalList = new ArrayList<>();
            for (JsonNode arrayElement : value)
                retvalList.add(arrayElement.asText());
            return retvalList;
        }
        return value.getNodeType() == JsonNodeType.NUMBER ? value.numberValue() : value.asText();
    }
Decode the given Base64URL-encoded value, parse the resulting JSON as a JSON
object, and return the map of member names to their values (each value being
represented as either a String, a Number, or a List of Strings).

@param split
           the value to decode and parse
@return the map of JSON member names to their String, Number, or String List
        value
@throws OAuthBearerIllegalTokenException
            if the given Base64URL-encoded value cannot be decoded or parsed
clients/src/main/java/org/apache/kafka/common/security/oauthbearer/internals/unsecured/OAuthBearerUnsecuredJws.java