[
https://issues.apache.org/jira/browse/FLINK-2788?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
Fabian Hueske updated FLINK-2788:
---------------------------------
Fix Version/s: (was: 0.10.0)
1.0.0
> Add type hint with TypeExtactor call on Hint Type
> -------------------------------------------------
>
> Key: FLINK-2788
> URL: https://issues.apache.org/jira/browse/FLINK-2788
> Project: Flink
> Issue Type: Improvement
> Components: Core
> Affects Versions: 0.10.0
> Reporter: Stephan Ewen
> Fix For: 1.0.0
>
>
> As per discussion with [~aljoscha]
> A very good and type safe way to supply type hints would be the following:
> Define a hint class that takes a generic parameter.
> {code}
> public abstract class TypeHint<T> {}
> {code}
> The hints would have the following method:
> {code}
> public DataSet<T> returns(TypeHint<T> hint);
> {code}
> It would be used like this:
> {code}
> DataSet<Sting> data = ...;
> data
> .flatMap( (String str, Collector<Integer> out) -> out.collect(str.length())
> )
> .returns( new TypeHint<Integer>() {})
> {code}
> This would create an inline subclass of the hint, from which the type could
> be extracted. The generics would ensure that it is typesafe.
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
