private static String getStringFromJsonNode(JsonNode jsonNode) {
        if (jsonNode.isContainerNode()) {
            return jsonNode.toString();
        }
        return jsonNode.asText();
    }
Creates a runtime converter which assuming input object is not null.
inlong-sort/sort-formats/format-rowdata/format-rowdata-json/src/main/java/org/apache/inlong/sort/formats/json/FieldToRowDataConverters.java