code: public static Specification<JpaDistributionSet> byIds(final Collection<Long> distids) {
          return (targetRoot, query, cb) -> {
              final Predicate predicate = targetRoot.<Long> get(JpaDistributionSet_.id).in(distids);
              targetRoot.fetch(JpaDistributionSet_.modules, JoinType.LEFT);
              targetRoot.fetch(JpaDistributionSet_.tags, JoinType.LEFT);
              targetRoot.fetch(JpaDistributionSet_.type, JoinType.LEFT);
              query.distinct(true);
              return predicate;
          };
      }
docs: {@link Specification} for retrieving {@link DistributionSet} with given
  {@link DistributionSet#getId()}s.
  
  @param distids
  to search
  @return the {@link DistributionSet} {@link Specification}