private Set<InternalDistributedMember> getAllRecipients(InternalCache cache, Map map) {
      Set recipients = new ObjectOpenHashSet();
      for (Object pr : map.keySet()) {
        PartitionedRegion partitionedRegion = (PartitionedRegion) cache.getRegion((String) pr);
        if (partitionedRegion != null && partitionedRegion.getRegionAdvisor() != null) {
          recipients.addAll(partitionedRegion.getRegionAdvisor().adviseDataStore());
        }
      }
      return recipients;
    }
Constructor : Creates and initializes the thread
geode-core/src/main/java/org/apache/geode/internal/cache/wan/parallel/ParallelGatewaySenderQueue.java