private boolean checkTime(char h0, char h1, char m0, char m1, char s0, char s1) {
        if (h0 == '0') {
            if (h1 < '0' || h1 > '9') {
                return false;
            }
        } else if (h0 == '1') {
            if (h1 < '0' || h1 > '9') {
                return false;
            }
        } else if (h0 == '2') {
            if (h1 < '0' || h1 > '4') {
                return false;
            }
        } else {
            return false;
        }

        if (m0 >= '0' && m0 <= '5') {
            if (m1 < '0' || m1 > '9') {
                return false;
            }
        } else if (m0 == '6') {
            if (m1 != '0') {
                return false;
            }
        } else {
            return false;
        }

        if (s0 >= '0' && s0 <= '5') {
            if (s1 < '0' || s1 > '9') {
                return false;
            }
        } else if (s0 == '6') {
            if (s1 != '0') {
                return false;
            }
        } else {
            return false;
        }

        return true;
    }
The value of a literal token, recorded as a string. For integers, leading 0x and 'l' suffixes are suppressed.
src/main/java/com/alibaba/fastjson/parser/JSONScanner.java