code: public static Specification<JpaDistributionSet> isDeleted(final Boolean isDeleted) {
          return (targetRoot, query, cb) -> cb.equal(targetRoot.<Boolean> get(JpaDistributionSet_.deleted), isDeleted);
  
      }
docs: {@link Specification} for retrieving {@link DistributionSet}s by its
  DELETED attribute.
  
  @param isDeleted
  TRUE/FALSE are compared to the attribute DELETED. If NULL the
  attribute is ignored
  @return the {@link DistributionSet} {@link Specification}