in my case I usually check the tests they write for each function I want to use.
Take CountTrigger as an example, if I want to customize my own way of counting, I will have a look at the test the write https://github.com/apache/flink/blob/8dfb9d00653271ea4adbeb752da8f62d7647b6d8/flink-streaming-java/src/test/java/org/apache/flink/streaming/runtime/operators/windowing/CountTriggerTest.java Then I understand how this function is expected to work, and then I write my own test with my expected result. Test is the best documentation I would say. Also there is an example folder in github. https://github.com/apache/flink/tree/master/flink-examples Best, Sendoh -- Sent from: http://apache-flink-user-mailing-list-archive.2336050.n4.nabble.com/