按照list中的时间排序

//实体类  AtomOrderList
//需要遍历的list   List<AtomOrderList> list

 private List<AtomOrderList> listSort(List<AtomOrderList> list) {
　　　　　//这边时间格式根据具体情况而定
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
        Date d1;
        Date d2;
        AtomOrderList temp = new AtomOrderList();
        //冒泡排序
        for (int i = 0; i < list.size(); i++) {
            for (int j = i+1; j < list.size(); j++) {
                ParsePosition pos1 = new ParsePosition(0);
                ParsePosition pos2 = new ParsePosition(0);
                if (null != list.get(i).getCreateDate() &&
                        null != list.get(j).getCreateDate()){
                    d1 = sdf.parse(list.get(i).getCreateDate(),pos1);
                    d2 = sdf.parse(list.get(j).getCreateDate(),pos2);
                    if (d1.before(d2)){
                        temp = list.get(i);
                        list.set(i,list.get(j));
                        list.set(j,temp);
                    }
                }
            }
        }
        System.out.println(list);
        return list;
    }