code: public long[] getSitesForPartitionsAsArray(int[] partitions) {
          ArrayList<Long> all_sites = new ArrayList<Long>();
          for (int p : partitions) {
              List<Long> sites = getSitesForPartition(p);
              for (long site : sites)
              {
                  all_sites.add(site);
              }
          }
          return longListToArray(all_sites);
      }
docs: Get the ids of all live sites that contain a copy of ANY of
  the given partitions.
  
  @param partitions A set of unique, non-null VoltDB
  partition ids.
  @return An array of VoltDB site ids.