@Override
  public ChangeSet add(final ChangeSet changeSet) {
    if (LOG.isDebugEnabled()) {
      LOG.debug("Add a change set: " + changeSet);
    }

    String groupId = changeSetMemberDao.generateChangeSetGroupId();
    changeSet.addAssignedUser(changeSet.getCreatedByUserGuid());

    // for consistency, always use the time service to set the created date
    changeSet.setCreatedDate(timeService.getCurrentTime());

    // if no state code was set the default is OPEN
    if (changeSet.getStateCode() == null) {
      changeSet.setStateCode(ChangeSetStateCode.OPEN);
    }

    getChangeSetMutator(changeSet).setObjectGroupId(groupId);
    return changeSetDao.add(changeSet);
  }
  /**
   * @param changeSet the change set to add members to
   * @param loadTuner the load tuner to use
   */
  protected void addMemberObjectsToChangeSet(final ChangeSet changeSet, final LoadTuner loadTuner) {
    if (!isLoadingMembersEnabled(loadTuner)) {
      return;
    }
    ChangeSetMutator changeSetWithMembers = getChangeSetMutator(changeSet);

    Collection<BusinessObjectGroupMember> businessObjectGroupMembers =
        changeSetMemberDao.findGroupMembersByGroupId(changeSet.getGuid());

    Collection<BusinessObjectMetadata> memberObjectsMetadata = Collections.emptySet();

    if (isLoadingMembersMetadataEnabled(loadTuner)) {
      memberObjectsMetadata =
          changeSetMemberDao.findBusinessObjectMetadataByGroupId(changeSet.getGuid());
    }
    Collection<ChangeSetMember> memberObjects =
        changeSetHelper.convertGroupMembersToChangeSetMembers(
            businessObjectGroupMembers, memberObjectsMetadata);

    changeSetWithMembers.setMemberObjects(memberObjects);
  }
  @Override
  public ChangeSet updateState(
      final String changeSetGuid, final ChangeSetStateCode stateCode, final LoadTuner loadTuner) {
    if (StringUtils.isEmpty(changeSetGuid) || stateCode == null) {
      throw new IllegalArgumentException(
          String.format(
              "Must specify change set GUID: %s and a state code: %s",
              new Object[] {changeSetGuid, stateCode}));
    }
    ChangeSet changeSet = changeSetDao.findByGuid(changeSetGuid);
    if (changeSet == null) {
      throw new EpServiceException(
          "No change set with GUID '" + changeSetGuid + "' could be found.");
    }
    changeSet.setStateCode(stateCode);

    final ChangeSet updatedChangedSet = changeSetDao.update(changeSet);

    addMemberObjectsToChangeSet(updatedChangedSet, loadTuner);

    return updatedChangedSet;
  }
  @Override
  public ChangeSet update(final ChangeSet changeSet, final LoadTuner loadTuner) {
    if (LOG.isDebugEnabled()) {
      LOG.debug("Update a change set: " + changeSet);
    }

    checkChangeAllowed(changeSet.getGuid());

    ChangeSet updatedChangedSet = changeSetDao.update(changeSet);

    addMemberObjectsToChangeSet(updatedChangedSet, loadTuner);

    return updatedChangedSet;
  }