android GET 请求在5.0版本的取不到数据，报IO异常兼容问题解决

public static ResponseContext invokeGet(String url,
			List<NameValuePair> headers) {
		ResponseContext result = new ResponseContext();
		try {
			RequestParams requestParams = new RequestParams();
			if (headers != null && headers.size() > 0) {
				requestParams.addBodyParameter(headers);
			}
			result = invokeRequest(url, requestParams,
					HttpRequest.HttpMethod.GET);
		} catch (Exception e) {
			String messageString = e.getMessage();
			result.setMessage(messageString);
			Log.e(TAG, messageString);
		}
		Log.d(TAG, "over");
		return result;
	}