Would you be interested in contributing a fix for that? Otherwise I'll probably fix work on that in the coming weeks.
On Wed, 2 Nov 2016 at 13:38 Yassine MARZOUGUI <y.marzou...@mindlytix.com> wrote: > Thank you Aljoscha for your quick response. > > Best, > Yassine > > 2016-11-02 12:30 GMT+01:00 Aljoscha Krettek <aljos...@apache.org>: > > Hi Yassine, > > regarding 1. The close() method of the RichFoldFunction will only be > called at the very end of your streaming job, so in practise it will never > be called. This is there because of batch jobs, where you have an actual > end in your processing. > > regarding 2. I'm afraid you came across a bug: > https://issues.apache.org/jira/browse/FLINK-3869. We can't change this > right now because we cannot break API instability but right at the end of > this issue I'm proposing a different solution that we'll hopefully get in > for the next release. > > Cheers, > Aljoscha > > On Wed, 2 Nov 2016 at 10:42 Yassine MARZOUGUI <y.marzou...@mindlytix.com> > wrote: > > Hi all, > > I have a couple questions about FoldFunction and WindowFunction: > > 1. When using a RichFoldFunction after a window as in > keyedStream.window().fold(new > RichFoldFunction()), is the close() method called after each window or > after all the windows for that key are fired? > > 2. When applying a FoldFunction to a window followed by a WindowFunction > via apply > <https://ci.apache.org/projects/flink/flink-docs-master/api/java/org/apache/flink/streaming/api/datastream/WindowedStream.html#apply-R-org.apache.flink.api.common.functions.FoldFunction-org.apache.flink.streaming.api.functions.windowing.WindowFunction->(R > initialValue, > FoldFunction > <https://ci.apache.org/projects/flink/flink-docs-master/api/java/org/apache/flink/api/common/functions/FoldFunction.html> > <T > <https://ci.apache.org/projects/flink/flink-docs-master/api/java/org/apache/flink/streaming/api/datastream/WindowedStream.html>,R> > foldFunction, > WindowFunction > <https://ci.apache.org/projects/flink/flink-docs-master/api/java/org/apache/flink/streaming/api/functions/windowing/WindowFunction.html> > <R,R,K > <https://ci.apache.org/projects/flink/flink-docs-master/api/java/org/apache/flink/streaming/api/datastream/WindowedStream.html> > ,W > <https://ci.apache.org/projects/flink/flink-docs-master/api/java/org/apache/flink/streaming/api/datastream/WindowedStream.html> > > function), why should the output of the WindowFunction be of the same > type as the input? It would be practical to have a different output type > sometimes, for example one would fold tuples in the FoldFunction and then > process the (only) aggregated tuple in the Window function and emit an > Integer. > > Best, > Yassine > > >
