@Test
 public void testCompare_NullFirstCollection() throws Exception {
   Collection collection = new ArrayList();
   assertTrue(
       COMPARATOR_HELPER.testComparatorResult(
           Constants.Comparator.PRIORITY_FIRST, entity.compare(null, collection)));
 }
 @Test
 public void testCompare_NullSecondCollection() throws Exception {
   Collection collection = new ArrayList();
   assertTrue(
       COMPARATOR_HELPER.testComparatorResult(
           Constants.Comparator.PRIORITY_SECOND, entity.compare(collection, null)));
 }
 @Test
 public void testCompare_NullBothCollections() throws Exception {
   assertTrue(
       COMPARATOR_HELPER.testComparatorResult(
           Constants.Comparator.EQUALS, entity.compare(null, null)));
 }