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Aljoscha Krettek commented on FLINK-4275: ----------------------------------------- This was changed to make it possible in the {{WindowOperator}} to check whether a state is empty. > Generic Folding, Reducing and List states behave differently from other state > backends > -------------------------------------------------------------------------------------- > > Key: FLINK-4275 > URL: https://issues.apache.org/jira/browse/FLINK-4275 > Project: Flink > Issue Type: Bug > Components: State Backends, Checkpointing, Streaming > Reporter: Gyula Fora > Priority: Critical > > In > https://github.com/apache/flink/commit/12bf7c1a0b81d199085fe874c64763c51a93b3bf > the expected behaviour of Folding/Reducing/List states have been changed to > return null instead of empty collections/default values. > This was adapted for the included state backends (Memory, FS, Rocks) but not > for the Generic state wrappers. As there are no tests for the Generic backend > using the StateBackendTestBase this didnt show. -- This message was sent by Atlassian JIRA (v6.3.4#6332)