How to check DataStream in flink is empty or having data
问题 I am new to Apache flink i have a datastream which implements a process function if certain conditions is met then the datastream is valid and if its not meeting the conditions i am writing it to sideoutput. I am able to print the datastream is it possible to check the datastream is empty or null.I tried using datastream.equals(null) method but its not working.Please suggest how to know whether a datastream is empty or not 回答1: By "empty", I assume you mean that no data is flowing. What are