### Question:
DefaultDiffUtilComparator implements DiffUtilComparator<MODEL> { @Override public boolean areContentsTheSame(MODEL oldModel, MODEL newModel) { return oldModel == newModel; }  @Override boolean areItemsTheSame(MODEL oldModel, MODEL newModel); @Override boolean areContentsTheSame(MODEL oldModel, MODEL newModel); @Override Object getChangePayload(MODEL oldModel, MODEL newModel);  }### Answer:
@Test public void areContentsTheSame_should_returnFalse_when_Not_equals() throws Exception { DefaultDiffUtilComparator<String> itemComparatorUnderTest = new DefaultDiffUtilComparator<>(); final boolean areContentsTheSame = itemComparatorUnderTest.areContentsTheSame("a", "b"); assertThat(areContentsTheSame, is(false)); }
@Test public void areContentsTheSame_should_returnTrue_when_equals() throws Exception { DefaultDiffUtilComparator<String> itemComparatorUnderTest = new DefaultDiffUtilComparator<>(); final boolean areContentsTheSame = itemComparatorUnderTest.areContentsTheSame("a", "a"); assertThat(areContentsTheSame, is(true)); }