### Question:
TimeUtils { public static long getTimeInHour(long ms) { return ms - ms % HOUR_IN_MILL; } private  TimeUtils(); static boolean isSecond(long ts); static long getTimeInHour(long ms);  }### Answer:
@Test public void testGetTimeInHour() throws ParseException { SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss"); Date date = sdf.parse("2019-04-18 15:32:33"); long timeInHour = TimeUtils.getTimeInHour(date.getTime()); Assert.assertEquals("2019-04-18 15:00:00", sdf.format(timeInHour)); }