字符串转json,解决gson转string数字或手机号改变问题

String str="{a=1111111,b=ssssssss,c=ddddddd}";
Gson gson = new Gson();
            JsonObject obj= gson.fromJson(str, JsonObject.class);
            for (String key : obj.keySet()) {
                map.put(key,obj.get(key).getAsString());
            }