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From: Eric Sosman <esosman@comcast-dot-net.invalid>
Newsgroups: comp.lang.java.programmer
Subject: Re: parallel stream with return
Date: Wed, 30 Sep 2015 08:01:07 -0400
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On 9/30/2015 2:35 AM, Philipp Kraus wrote:
> Hello,
>
> I'm new with the Java 1.8 parallel stream, so I have got a problem:
>
> I have the sequential for loop:
>
> final Set<myClass> x = new HashSet<>();
> for(int i=0; i < value; ++i)
>      x.add( this.generate() );
>
> And I would like to do this with a parallel stream which collects each generate return value into the set.
> My first try was to use a synchronized HashSet and
>
> IntStream.range(0, value).parallel().forEach( i-> { x.add(this.generate()) } );
>
> After that I try to swap forEach to map, but at this I must return an int value and not a myClass value, so how can I do n generate calls in parallel and collect the results into a hashset?

     I think you want java.util.stream.Collectors, either toSet()
or toCollection().

-- 
esosman@comcast-dot-net.invalid
"Don't be afraid of work. Make work afraid of you." -- TLM