Java判断身份证号码是否正确

        首先写一个方法来判断是否是闰年

 public static boolean isLeapYear(String year) {
    Long yearL = Long.parseLong(year);
    if ((yearL % 4 == 0) && (yearL % 100 != 0) || (yearL % 400 == 0)) {
      return true;
    }
    return false;
  }

      写一个方法获取一年中某个月对应的天数

public static int getDays(String year, int month) {
    int days = 0;
    switch (month) {
    case 1:
      days = 31;
      break;
    case 3:
      days = 31;
      break;
    case 5:
      days = 31;
      break;
    case 7:
      days = 31;
      break;
    case 8:
      days = 31;
      break;
    case 10:
      days = 31;
      break;
    case 12:
      days = 31;
      break;
    case 2:
      if (isLeapYear(year))
        days = 29;
      else
        days = 28;
      break;
    default:
      days = 30;
    }
    return days;
  }

        有了上面的两个方法，在下面的方法中进行调用来判断身份证号码是否是正确

public static boolean validateIdNumber(String idNumber) {
    //
    Pattern p1 = Pattern.compile("(\\d{17}[0-9xX]|\\d{14}[0-9xX])");
    Matcher matcher = p1.matcher(idNumber);
    if (matcher.matches()) {
      Pattern p2 = Pattern.compile("\\d{6}(\\d{8}).*"); // 用于提取出生日字符串
      Pattern p3 = Pattern.compile("(\\d{4})(\\d{2})(\\d{2})");// 用于将生日字符串进行分解为年月日
      Matcher matcher2 = p2.matcher(idNumber);
      boolean flag = matcher2.find();
      if (flag) {
        String date = matcher2.group(1);
        Matcher matcher3 = p3.matcher(date);
        if (matcher3.find()) {
          String year = matcher3.group(1);
          int month = Integer.parseInt(matcher3.group(2));
          int day = Integer.parseInt(matcher3.group(3));
          if (month < 1 || month > 12) {
            return false;
          }
          if (day > getDays(year, month) || day < 1) {
            return false;
          }
          return true;
        }
      }
    }
    return false;
  }

        这个方法基本能满足验证身份证号码是否符合规则，不过也有缺陷没有办法来判断地区行政代码是否正确。因为地区代码会有调整，很难控制。