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From Timo Walther <twal...@apache.org>
Subject Re: Test example and lambdas
Date Mon, 07 Aug 2017 11:34:37 GMT
Hi,

Row is very special data type, because Flink cannot extract the field 
types automatically based on Java generics. By default it is serialized 
by Kryo, you need to specify the field types using 
Typles.ROW(Types.STRING, ...) and pass this information in your 
`.returns()` methods instead of `Row.class`.

Lambdas are sometimes a problem for Flink, see 
https://ci.apache.org/projects/flink/flink-docs-release-1.4/dev/java8.html.

In your example it might makes sense to use the Table API for 
pre-processing. The Table API has a built-in CSV input format and deals 
with all the type handling for you. You can convert a table back to 
DataStream.

Regards,
Timo


Am 05.08.17 um 13:49 schrieb Егор Литвиненко:
> > No errors, and no
> data in table.
>
> 2017-08-05 14:49 GMT+03:00 Егор Литвиненко <e.v.litvinenko.1@gmail.com

> <mailto:e.v.litvinenko.1@gmail.com>>:
>
>     Hi
>
>     I try to test Flink and have a problems.
>     Why this example doesn't work -
>     https://github.com/egorlitvinenko/testparsing/blob/master/test-flink/src/main/java/org/egorlitvinenko/testflink/StreamingJob9C.java
>     <https://github.com/egorlitvinenko/testparsing/blob/master/test-flink/src/main/java/org/egorlitvinenko/testflink/StreamingJob9C.java>
>     Logs - https://pastebin.com/iuBZhfeG <https://pastebin.com/iuBZhfeG>
>     No errors, and no
>
>     One more question. Examples intentionally use anonymous classes,
>     instead of lambdas. Because with lambda it also doesn't work. I
>     did small investigation and found out that Flink has different
>     processing for lambdas. And in one moment when Flink processes
>     types, they are empty.  Do you have full lambdas support?
>
>     In best regards, Egor Litvinenko.
>
>


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