query.from(qArtifact)
.where(qArtifact.group.groupId.eq(groupId))
.where(qArtifact.artifactId.eq(artifactId));
return query.uniqueResult(qArtifact);
}
@Override
public List<Artifact> listMostFollowedArtifacts(int limit) {
JPAQuery query = new JPAQuery(getEntityManager());