List<Map<>>排序（根据日期）

Collections.sort(mapBroadcom, new Comparator<Map<Integer, String>>()
{
            public int compare(Map<Integer, String> o1, Map<Integer, String> o2)
            {
            Date date1 = null;
            Date date2 = null;
            try
{
date1 = format2.parse(o1.get(15));
date2 = format2.parse(o2.get(15));
} catch (ParseException e)
{
e.printStackTrace();
}
            return date1.compareTo(date2);
            }
});