### Question:
RegexUtil { public static boolean isBankCard(String card) { if (card == null) return false; card = card.replace(" ", ""); return card.matches("^\\d{16,19}$"); }  static boolean isIdentityNumber(String num); static boolean isCellphoneNumber(String num); static boolean isCellphoneNumber(String num, boolean virtual); static boolean isPhoneNumber(String num); static boolean isAuthCode(String num); static boolean isAuthCode(String num, int min, int max); static boolean isName(String name); static boolean isVehicleLicence(String license); static boolean isEmail(String email); static boolean isBankCard(String card); static boolean isLowerMoney(String money); static boolean isInteger(String integer, long min, long max); static boolean isPassword(String password); static boolean isComplexPassword(String password); static boolean isIpAddress(String address); static boolean isIp4Address(String address); static boolean isIp6Address(String address);  }### Answer:
@Test public void isBankCard() { assertTrue(RegexUtil.isBankCard("6222600260001072444")); }