if (isRootLayer() && target.isAlternateFlow()) { continue; }
    private List getStackingContextLayers(int which) {        List result = new ArrayList();                List children = getChildren();        for (int i = 0; i < children.size(); i++) {            Layer target = (Layer)children.get(i);            if (target.isStackingContext()) {                if (which == NEGATIVE && target.getZIndex() < 0) {                    result.add(target);                } else if (which == POSITIVE && target.getZIndex() > 0) {                    result.add(target);                } else if (which == ZERO) {                    result.add(target);                }            }        }                return result;    }