How can i detect pattern a+b+ with Flink CEP

[Mohammad Hossein Gerami]

Hi to all of you
I want to detect pattern like a+b+. but i think oneormore() not working for
me.
i sent my question to stackoverflow.
https://stackoverflow.com/questions/57977009/how-can-i-detect-pattern-ab-with-flink-cep
please help me!
thanks