### Question:
DaysByteXmlAdapter extends XmlAdapter<ClientDaysSortedSetWrapper, SortedSet<Byte>> { @Override public ClientDaysSortedSetWrapper marshal(SortedSet<Byte> v) throws Exception { ClientDaysSortedSetWrapper result = null; if(v != null && !v.isEmpty()){ SortedSet<String> strings = new TreeSet<String>(); for(Byte value : v) strings.add(value.toString()); result = new ClientDaysSortedSetWrapper(strings); } return result; }  @Override SortedSet<Byte> unmarshal(ClientDaysSortedSetWrapper v); @Override ClientDaysSortedSetWrapper marshal(SortedSet<Byte> v);  }### Answer:
@Test public void marshal_nullValue_nullValue() throws Exception { ClientDaysSortedSetWrapper actual = objectUnderTest.marshal(null); assertNull(actual); }
@Test public void marshal_empty_nullValue() throws Exception { ClientDaysSortedSetWrapper actual = objectUnderTest.marshal(new TreeSet<Byte>()); assertNull(actual); }
@Test public void marshal_someDays_wrapper() throws Exception { ClientDaysSortedSetWrapper expected = createClientDaysSortedSetWrapperWithDays(); ClientDaysSortedSetWrapper actual = objectUnderTest.marshal(TEST_DAYS_AS_BYTES); assertEquals(expected, actual); }