presto-hive/src/main/java/io/prestosql/plugin/hive/util/HiveUtil.java/HiveUtil/getDecimalType
class HiveUtil:    public static Optional<DecimalType> getDecimalType(String hiveTypeName)
    {
        Matcher matcher = SUPPORTED_DECIMAL_TYPE.matcher(hiveTypeName);
        if (matcher.matches()) {
            int precision = parseInt(matcher.group(DECIMAL_PRECISION_GROUP));
            int scale = parseInt(matcher.group(DECIMAL_SCALE_GROUP));
            return Optional.of(createDecimalType(precision, scale));
        }
        else {
            return Optional.empty();
        }
    }