map取的值转为list

String params = request.getParameter("params");
Map<String,String> map = (Map)JSON.parse(params);
//将map里的list值取出来  转为object  
Object objList = (Object)map.get("list");
JSONArray array = JSONArray.fromObject(objList);
List<Map> listMap = JSONArray.toList(array,new HashMap(),new JsonConfig());