### Question:
TimeUtils { public static boolean isSecond(long ts) { return (ts & SECOND_MASK) == 0; } private  TimeUtils(); static boolean isSecond(long ts); static long getTimeInHour(long ms);  }### Answer:
@Test public void testIsSecond() { Assert.assertFalse(TimeUtils.isSecond(System.currentTimeMillis())); Assert.assertTrue(TimeUtils.isSecond(System.currentTimeMillis() / 1000)); }