@Override
    public String generate() {
        String voucherNumber = makeVoucherNumber();

        return String.format(VOUCHER_NUMBER_FORMAT,
                makeFirstFields(voucherNumber),
                makeSecondFields(voucherNumber),
                makeThirdFields(voucherNumber),
                makeFourthFields(voucherNumber)
        );
    }
@Test
    void 번호는_한_필드에_6개씩_총_4개의_필드로_이루어진다() {
        // given
        int delimiterSize = 3;
        int numberSize = 24;

        // when
        String numbers = voucherNumberUUIDGenerator.generate();

        // then
        String[] fields = numbers.split("-");
        assertSoftly(softly -> {
            softly.assertThat(fields.length).isEqualTo(4);
            softly.assertThat(fields[0].length()).isEqualTo(6);
            softly.assertThat(numbers.length()).isEqualTo(delimiterSize + numberSize);
        });
    }