### Question:
XrayGogglesModel extends Observable implements Cloneable { public void setScreenPosition(ScreenPosition upperLeft, ScreenPosition upperRight, ScreenPosition lowerLeft, ScreenPosition lowerRight) { if (myValidator == null || myValidator.isValid(upperLeft, upperRight, lowerLeft, lowerRight)) { myUpperLeft = upperLeft; myUpperRight = upperRight; myLowerLeft = lowerLeft; myLowerRight = lowerRight; setChanged(); notifyObservers(SCREEN_POSITION); } }  @Override XrayGogglesModel clone(); GeographicPosition getCenterGeo(); ScreenPosition getLowerLeft(); GeographicPosition getLowerLeftGeo(); ScreenPosition getLowerRight(); GeographicPosition getLowerRightGeo(); ScreenPosition getUpperLeft(); GeographicPosition getUpperLeftGeo(); ScreenPosition getUpperRight(); GeographicPosition getUpperRightGeo(); Geometry getWindowGeometry(); void setGeoPosition(GeographicPosition upperLeft, GeographicPosition upperRight, GeographicPosition lowerLeft,
            GeographicPosition lowerRight, GeographicPosition center); void setScreenPosition(ScreenPosition upperLeft, ScreenPosition upperRight, ScreenPosition lowerLeft,
            ScreenPosition lowerRight); void setValidator(XrayModelValidator validator); void setWindowGeometry(Geometry windowGeometry); static final String GEO_POSITION; static final String SCREEN_POSITION; static final String XRAY_GOGGLES; }### Answer:
@Test public void testSetScreenPosition() { EasyMockSupport support = new EasyMockSupport(); Observer observer = createObserver(support, XrayGogglesModel.SCREEN_POSITION); support.replayAll(); ScreenPosition upperLeft = new ScreenPosition(10, 11); ScreenPosition upperRight = new ScreenPosition(11, 11); ScreenPosition lowerLeft = new ScreenPosition(10, 10); ScreenPosition lowerRight = new ScreenPosition(11, 10); XrayGogglesModel model = new XrayGogglesModel(); model.addObserver(observer); model.setScreenPosition(upperLeft, upperRight, lowerLeft, lowerRight); assertEquals(upperLeft, model.getUpperLeft()); assertEquals(upperRight, model.getUpperRight()); assertEquals(lowerLeft, model.getLowerLeft()); assertEquals(lowerRight, model.getLowerRight()); support.verifyAll(); }