public UidResult getUid(String accessToken)
    {
    	UidResult result = new UidResult();
    	if (this.uid != null) {
    		result.setRv(ERROR_SUCCESS);
    		result.setUid(this.uid);
    		return result;
    	}
    	
        String respStr = getUidStr(accessToken, SINA_GET_UID);
        if (respStr == null || "".equals(respStr)) {
        	result.setRv(ERROR_NETWORK_CALL);
        	return result;
        }
        Object obj = JSON.parse(respStr);
		JSONObject msg = (JSONObject)obj;
        
		
		int errorCode = msg.getIntValue("error_code");
        if (errorCode > 0) {
            result.setRv(errorCode);
            result.setErrmsg(msg.getString("error_description"));
        } else {
            result.setRv(ERROR_SUCCESS);
            String uid = msg.getString("uid");
            result.setUid(uid);
            this.uid = uid;
        }
        return result;
    }