身份證號合法性校驗

public static boolean isLegalIDCard(String idCard) {
	boolean res = false;
	if (!StringUtils.isBlank(idCard)) {
	    // 校驗規則(15或是18位身份證號碼)
	    String regex = "(^[1-9]\\d{5}(18|19|20)\\d{2}((0[1-9])|(10|11|12))(([0-2][1-9])|10|20|30|31)\\d{3}[0-9Xx]$)|" + "(^[1-9]\\d{5}\\d{2}((0[1-9])|(10|11|12))(([0-2][1-9])|10|20|30|31)\\d{3}$)";
	    boolean matches = idCard.matches(regex);
	    // 判斷第18位校驗值
	    if (matches) {
	        if (idCard.length() == 18) {
	            char[] idCardArray = idCard.toCharArray();
	            // 前十七位加權因子
	            int[] idCardWi = {7, 9, 10, 5, 8, 4, 2, 1, 6, 3, 7, 9, 10, 5, 8, 4, 2};
	            // 除以11後,可能產生的11位餘數對應的驗證碼
	            String[] idCardY = {"1", "0", "X", "9", "8", "7", "6", "5", "4", "3", "2"};
	            int total = 0;
	            for (int i = 0; i < idCardWi.length; i++) {
	                int count = Integer.parseInt(String.valueOf(idCardArray[i])) * idCardWi[i];
	                total += count;
	            }
	            // 最後一位校驗碼
	            int idCardModify = total % 11;
	            if (idCardY[idCardModify].toUpperCase().equals(String.valueOf(idCardArray[17]).toUpperCase())) {
	                res = true;
	            } else {
	                System.out.println(idCardY[idCardModify].toUpperCase());
	                res = false;
	            }
	        } else {
	            res = true;
	        }
	    }
	}
	return res;
}