### Question:
EmptyModelAdjuster implements ModelAdjuster { @Override public @Nullable Object adjust(@Nullable Object obj) { return obj; }  @Override @Nullable Object adjust(@Nullable Object obj);  }### Answer:
@Test public void nullReturnsNull() throws Exception { Assert.assertNull("null returns null", emptyModelAdjuster.adjust(null)); }
@Test public void sameObject() throws Exception { final Object obj = new Object(); Assert.assertEquals("return the same object", obj, emptyModelAdjuster.adjust(obj)); }