sharedpreferences如何保存对象

    public static void getJsonStringByEntity(Context context, Object object) {
         String strJson = "";
         Gson gson = new Gson();
         strJson = gson.toJson(object);
         saveSharePlayList(context,strJson);
    }

 public static PlayList getfromJson(Context context){
        PlayList list = null;
        String str = readSharePlayList(context);
        if(str!=null){
            Gson gson=new Gson();
            list = gson.fromJson(str, new TypeToken<PlayList>(){}.getType());
        }
        return list;
    }