presto-kafka/src/main/java/io/prestosql/plugin/kafka/KafkaRecordSet.java/KafkaRecordSet/checkFieldType
class KafkaRecordSet:        private void checkFieldType(int field, Class<?> expected)
        {
            Class<?> actual = getType(field).getJavaType();
            checkArgument(actual == expected, "Expected field %s to be type %s but is %s", field, expected, actual);
        }