### Question:
Decorator extends Group { protected void fireShow(final double x, final double y) { if (null != callback) { callback.onShow(x, y); } } Decorator(final ItemCallback callback); Decorator setPadding(final double padding); Decorator setItemCallback(final ItemCallback callback); IPrimitive<?> build(final IPrimitive<?> item,
                               final double width,
                               final double height); Rectangle createRectangle(final double width,
                                     final double height); Decorator show(final double x,
                          final double y); Decorator hide();  }### Answer:
@Test public void testFireShow() { decorator.fireShow(3.0, 5.0); verify(callback).onShow(3.0, 5.0); }