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https://issues.apache.org/jira/browse/FLINK-3002?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15004298#comment-15004298
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Nick Dimiduk commented on FLINK-3002:
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Is the desire for a general {{Maybe}}, or a slightly more restricted
{{Optional}} type?
For what it's worth, I recently implemented a local solution for the general
problem of error handling I [asked
about|https://mail-archives.apache.org/mod_mbox/flink-user/201511.mbox/%3CCANZa%3DGvfFxayAP1TG8U85TAY%2B4%3D6oj8he0SyGXg1Ys5cELY2rw%40mail.gmail.com%3E]
on the user list earlier this week in the form of my own {{Maybe}} type. My
{{Maybe}} is actually a triple of {{(IN, OUT, Throwable)}}, expressed as a Java
Generic. Type resolution on the generic is not at all obvious to me; I don't
know the Flink APIs well enough to pursue a {{MaybeTypeInfo}}. My solution was
to define {{MaybeFoo}} classes with the purpose only of specifying generic
arguments. I tried a number of other solutions, but always I ran into issues
with type erasure. For example, I have {{class MaybeFoo extends Maybe<byte[],
Foo>}} for attempted reads of {{Foo}} objects off of a Kafka topic.
I'm quite interested in a general solution provided by the framework and I'm
happy to share my code if that's of use.
> Add an EitherType to the Java API
> ---------------------------------
>
> Key: FLINK-3002
> URL: https://issues.apache.org/jira/browse/FLINK-3002
> Project: Flink
> Issue Type: New Feature
> Components: Java API
> Affects Versions: 0.10
> Reporter: Stephan Ewen
> Assignee: Vasia Kalavri
> Fix For: 1.0
>
>
> Either types are recurring patterns and should be serialized efficiently, so
> it makes sense to add them to the core Java API.
> Since Java does not have such a type as of Java 8, we would need to add our
> own version.
> The Scala API handles the Scala Either Type already efficiently. I would not
> use the Scala Either Type in the Java API, since we are trying to get the
> {{flink-java}} project "Scala free" for people that don't use Scala and o not
> want to worry about Scala version matches and mismatches.
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