public void testTo12HourClock() throws Exception {
   assertEquals(0, TimeUtil.to12HourClock(0));
   assertEquals(8, TimeUtil.to12HourClock(8));
   assertEquals(0, TimeUtil.to12HourClock(12));
   assertEquals(8, TimeUtil.to12HourClock(20));
   try {
     TimeUtil.to12HourClock(24);
     fail();
   } catch (AssertionError e) {
     // ok
   }
   try {
     TimeUtil.to12HourClock(-1);
     fail();
   } catch (AssertionError e) {
     // ok
   }
 }
 public void testTo12HourClock1() throws Exception {
   assertEquals("12:00:00", TimeUtil.to12HourClock("00:00:00"));
   assertEquals("8:05:03", TimeUtil.to12HourClock("08:05:03"));
   assertEquals("12:00:00", TimeUtil.to12HourClock("12:00:00"));
   assertEquals("8:00:00", TimeUtil.to12HourClock("20:00:00"));
 }