Collector groupingByConcurrent metodu

Giriş
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import java.util.stream.Collectors;

Örnek 

Şöyle yaparız.

List<Event> getNearEventsConcurrent(int number, List<Event> events, String targetLocation) {
        
  Map<Integer, Set<Event>> distanceEventsMap = events.stream().parallel().
    collect(Collectors.groupingByConcurrent(
      event -> evaluateLocationProximity(event.location(), targetLocation), 
      ConcurrentSkipListMap::new, 
      Collectors.toCollection(() -> new TreeSet<>(
        Comparator.comparingInt(Event::eventRankId)))));
  
  return distanceEventsMap.values()
    .stream()
    .flatMap(Set::stream)
    .limit(number)
    .collect(Collectors.toList());
}