// 遍历先获取起点,即没有父id的点

String first;

        boolean flag = true;
        String temp = first;
        while (flag) {
            Iterator<Points> iterator = pointsList.iterator();
            while(iterator.hasNext()){
                Points point = iterator.next();
                if (point.getLcd().equals(temp)) {
                    temp = point.getPosOffLcd();
                    resultList.add(point);
                    iterator.remove();
                    break;
                }
            }

            if (temp.isEmpty()) {
                flag = false;
            }
        }