Hub Exception. error Code 字段
Provides the HTTP error code, if applicable.
This value will be a 6 digital error code such as 404001 if the service provided one in response message to the HTTP request. Otherwise it will be a 3 digit status code such as 404.
For AMQP operations such as sending cloud to device messages, receiving message feedback, and getting file upload notifications, this field will not be populated.
protected int errorCode