Shortcuts on Collections to create Streams
Thiago Henrique Hupner
thihup at gmail.com
Wed Mar 3 21:53:14 UTC 2021
They have added the Stream#toList in JDK 16:
https://download.java.net/java/early_access/jdk16/docs/api/java.base/java/util/stream/Stream.html#toList()
Em qua., 3 de mar. de 2021 às 18:45, Zs. <gzsombor at gmail.com> escreveu:
> Hi,
>
> As Collection already has a default implementation for 'forEach', I'm
> wondering why there is no similar shortcuts for a couple of repeating
> patterns around the Collection <--> Stream transitions?
> For example, if you could write:
> collection.map(...) instead of collection.stream().map(...);
> collection.filter(...) instead of collection.stream().filter(...);
> Or for the other direction:
> stream.toList() instead of stream.collect(Collectors.toList())
> stream.toSet() instead of stream.collect(Collectors.toSet())
>
> They are heavily used even in OpenJDK's source code:
>
> -
>
> https://github.com/search?q=stream%5C%28%5C%29.filter%28+repo%3Aopenjdk%2Fjdk+language%3AJava&type=Code&ref=advsearch&l=Java&l=
> - 380 results, unfortunately with false matches from javax.xml.stream.
> StreamFilter
> -
>
> https://github.com/search?q=stream%5C%28%5C%29.map%5C%28%5C%29+repo%3Aopenjdk%2Fjdk&type=Code
> - 559 results, unfortunately with false matches from comments or
> streams().mapToInt or not related code
>
>
> -
>
> https://github.com/openjdk/jdk/search?q=collect%28Collectors.toList%28%29%29
> - 367 results
> -
>
> https://github.com/openjdk/jdk/search?q=collect%28Collectors.toSet%28%29%29
> - 117 results
>
> Any particular reason, why adding these - 4 or more - default method to a
> collection deemed unnecessary or harmful? Unfortunately I haven't been able
> to find the answers for this question using internet searches.
>
> Thanks,
> Zsombor
>
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