Java正则校验统一社会信用代码

可以使用以下正则表达式来校验统一社会信用代码：

public static boolean isValidSocialCreditCode(String code) {
    String regex = "^[0-9A-Z]{18}$";
    if (!code.matches(regex)) {
        return false;
    }

    // 校验第 18 位
    int[] weights = { 1, 3, 9, 27, 19, 26, 16, 17, 20, 29, 25, 13, 8, 24, 10, 30, 28 };
    char[] chars = code.toCharArray();
    int sum = 0;
    for (int i = 0; i < weights.length; i++) {
        char c = chars[i];
        int num = 0;
        if (c >= '0' && c <= '9') {
            num = c - '0';
        } else if (c >= 'A' && c <= 'Z') {
            num = c - 'A' + 10;
        }
        sum += num * weights[i];
    }
    int remainder = sum % 31;
    char checkCode = remainder == 0 ? '0' : (char) (31 - remainder + '0');
    return checkCode == chars[17];
}

这个方法会先校验字符串长度和格式是否正确，然后再根据统一社会信用代码的规则校验第18位校验码是否正确。