public void addRepoDefinitionEntities(List<RepoDefinitionEntity> repoDefinitionEntities) {
    this.repoDefinitionEntities.addAll(repoDefinitionEntities);
    for (RepoDefinitionEntity repoDefinitionEntity : repoDefinitionEntities) {
      repoDefinitionEntity.setRepoOs(this);
    }
  }
Update one-to-many relation without rebuilding the whole entity

@param repoDefinitionEntities list of many-to-one entities
ambari-server/src/main/java/org/apache/ambari/server/orm/entities/RepoOsEntity.java