### Question:
DateUtil { public static boolean isDate(String date) { return isDate(date, PATTERN_HAVE_TIME); }  static boolean isDate(String date); static boolean isDate(String date, String pattern); static String format(Date date); static String formatTime(Date date); static String format(Date date, String pattern); static String getCurDatetime(); static String getCurDatetime(String pattern); static String getCurDatetime(String pattern, ZoneId zoneId); static Date getCurDate(String date, String pattern); static boolean isSameDay(Date date1, Date date2); static boolean isSameDay(Calendar cal1, Calendar cal2); static Date addYears(Date date, int year); static Date addMonths(Date date, int month); static Date addWeeks(Date date, int amount); static Date addDays(Date date, int amount); static Date addHours(Date date, int amount); static Date addMinutes(Date date, int amount); static Date addSeconds(Date date, int amount); static Date addMilliseconds(Date date, int amount); static int daysBetween(Date date1, Date date2, String pattern); static boolean isWeekEnd(Date date); Date tradingTomorrowDay(Date date, int n); static int daysBetween(Date date1, Date date2); static Long getTimestampDiff(Date time1, Date time2); static long getTimestamp(); static String getAgeByBirthday(Date birthday); static long getAgeByBirthday(String birthday, String pattern); static String getNowUTCTimeStamp(); static String timeZone(Date date);  }### Answer:
@Test void isDate() { System.out.println(DateUtil.isDate("2018-02-29", "yyyy-MM-dd")); }