KeyboardOperationMoveDown extends KeyboardOperationMove { @Override SelectionExtension getSelectionExtension() { return SelectionExtension.DOWN; } KeyboardOperationMoveDown(final GridLayer gridLayer);  KeyboardOperationMoveDown(final GridLayer gridLayer,
                                     final GridLienzoScrollable panel); @Override int getKeyCode();  }
@Test public void testGetSelectionExtension() { final SelectionExtension actual = keyboardOperation.getSelectionExtension(); assertEquals(SelectionExtension.DOWN, actual); }