}
@Test
public void testContains() {
IShape sh1 = ShapeFactory.createRectangle();
IShape sh2 = ShapeFactory.createRectangle();
IShape sh3 = ShapeFactory.createRectangle();
IShape sh4 = ShapeFactory.createRectangle();
drawing.getShapes().add(sh1);
drawing.getShapes().add(sh2);
drawing.getShapes().add(sh3);