### Question:
DropdownLayoutUpdater implements RowLayoutUpdater { @Override public void updateRowLayout(int dropdownLayoutId) { dataSetAdapterBuilder.setDropdownLayoutId(dropdownLayoutId); } DropdownLayoutUpdater(DataSetAdapterBuilder dataSetAdapterBuilder); @Override void updateRowLayout(int dropdownLayoutId);  }### Answer:
@Test public void whenUpdatingRowLayout_thenSetDropdownLayoutOnDataSetAdapterBuilder() { int layoutId = anyInteger(); DropdownLayoutUpdater dropdownLayoutUpdater = new DropdownLayoutUpdater(dataSetAdapterBuilder); dropdownLayoutUpdater.updateRowLayout(layoutId); verify(dataSetAdapterBuilder).setDropdownLayoutId(layoutId); }