T - Required information type when the task succeeds. This may be Void if nothing
           but the task success developer should know.E - Error type when the task succeeds. This may be Void if nothing but the task
           fails developer should know.public interface OnResultListener<T,E>
OnResultListener is a result listener of task. Developer should implement this interface
 to handle the result.| Modifier and Type | Method and Description | 
|---|---|
void | 
onFailure(E error)
Invoked with error information when the task fails. 
 | 
void | 
onSuccess(T result)
Invoked with required information when the task succeeds. 
 |