json中MorphDynaBean的取值

返回的json数据如下：

{"key":"success","message":"查询成功","relationKey":[{"keybd_state":1,"keybd_code":"cXzDdfOcHC"}],"success":true}

JSONObject jsonObject=JSONObject.fromObject(returnStr);
		MorphDynaBean bean = (MorphDynaBean) JSONArray.toList((JSONArray) jsonObject.get("relationKey")).get(0);
		int keybd_state = (int) bean.get("keybd_state");