请参考以下代码：

LayerTree layertree = new LayerTree(doc);

LayerNode root = layertree.getRootNode();

int children_count = root.getChildrenCount();

root.removeChild(children_count -1);

LayerNode child = root.getChild(children_count – 2);

LayerNode child0 = root.getChild(0);

child.moveTo(child0, 0);

child.addChild(0, "AddedLayerNode", true);

child.addChild(0, "AddedNode", false);