* Tests the methods of NullShape.
*/
public void testMethods() {
NullElement elem = NullElement.getInstance();
elem.recalculateSize(drawingContext);
elem.draw(drawingContext);
assertFalse(elem.isVisible(new Rectangle(0, 0, 1000, 1000)));
assertFalse(elem.isVisible(null));
assertEquals(NullSelection.getInstance(), elem.getSelection(operations));
assertNull(elem.getModelElement());
assertNull(elem.getLabelAt(1, 2));