protected void saveSolution(org.hibernate.Session hibSession) {
    TimetableManager owner =
        TimetableManager.findByExternalId(
            getModel().getProperties().getProperty("General.OwnerPuid"));
    Collection exams = org.unitime.timetable.model.Exam.findAll(iSessionId, iExamTypeId);
    Hashtable<Long, ExamEvent> examEvents = new Hashtable();
    for (Iterator i =
            hibSession
                .createQuery(
                    "select e from ExamEvent e where e.exam.session.uniqueId=:sessionId and e.exam.examType.uniqueId=:examTypeId")
                .setLong("sessionId", iSessionId)
                .setLong("examTypeId", iExamTypeId)
                .iterate();
        i.hasNext(); ) {
      ExamEvent e = (ExamEvent) i.next();
      examEvents.put(e.getExam().getUniqueId(), e);
    }
    iProgress.setPhase("Saving assignments...", exams.size());
    Hashtable examTable = new Hashtable();
    for (Iterator i = exams.iterator(); i.hasNext(); ) {
      iProgress.incProgress();
      org.unitime.timetable.model.Exam exam = (org.unitime.timetable.model.Exam) i.next();
      ExamAssignment oldAssignment = new ExamAssignment(exam);
      exam.setAssignedPeriod(null);
      exam.setAssignedPreference(null);
      exam.getAssignedRooms().clear();
      ExamEvent event = examEvents.get(exam.getUniqueId());
      if (event != null) hibSession.delete(event);
      for (Iterator j = exam.getConflicts().iterator(); j.hasNext(); ) {
        ExamConflict conf = (ExamConflict) j.next();
        hibSession.delete(conf);
        j.remove();
      }
      Exam examVar = null;
      for (Exam x : getModel().variables()) {
        if (exam.getUniqueId().equals(x.getId())) {
          examVar = x;
          break;
        }
      }
      if (examVar == null) {
        iProgress.warn("Exam " + getExamLabel(exam) + " was not loaded.");
        if (oldAssignment.getPeriodId() != null) {
          SubjectArea subject = null;
          Department dept = null;
          for (Iterator j = new TreeSet(exam.getOwners()).iterator(); j.hasNext(); ) {
            ExamOwner xo = (ExamOwner) j.next();
            subject = xo.getCourse().getSubjectArea();
            dept = subject.getDepartment();
            break;
          }
          ChangeLog.addChange(
              hibSession,
              owner,
              exam.getSession(),
              exam,
              exam.getName()
                  + " ("
                  + oldAssignment.getPeriodAbbreviation()
                  + " "
                  + oldAssignment.getRoomsName(", ")
                  + " &rarr; N/A)",
              ChangeLog.Source.EXAM_SOLVER,
              ChangeLog.Operation.UNASSIGN,
              subject,
              dept);
        }
        continue;
      }
      examTable.put(examVar.getId(), exam);
      ExamPlacement placement = getAssignment().getValue(examVar);
      if (placement == null) {
        iProgress.warn("Exam " + getExamLabel(exam) + " has no assignment.");
        if (oldAssignment.getPeriodId() != null) {
          SubjectArea subject = null;
          Department dept = null;
          for (Iterator j = new TreeSet(exam.getOwners()).iterator(); j.hasNext(); ) {
            ExamOwner xo = (ExamOwner) j.next();
            subject = xo.getCourse().getSubjectArea();
            dept = subject.getDepartment();
            break;
          }
          ChangeLog.addChange(
              hibSession,
              owner,
              exam.getSession(),
              exam,
              exam.getName()
                  + " ("
                  + oldAssignment.getPeriodAbbreviation()
                  + " "
                  + oldAssignment.getRoomsName(", ")
                  + " &rarr; N/A)",
              ChangeLog.Source.EXAM_SOLVER,
              ChangeLog.Operation.UNASSIGN,
              subject,
              dept);
        }
        continue;
      }
      ExamPeriod period = new ExamPeriodDAO().get(placement.getPeriod().getId());
      if (period == null) {
        iProgress.warn(
            "Examination period "
                + placement.getPeriod().getDayStr()
                + " "
                + placement.getPeriod().getTimeStr()
                + " not found.");
        if (oldAssignment.getPeriodId() != null) {
          SubjectArea subject = null;
          Department dept = null;
          for (Iterator j = new TreeSet(exam.getOwners()).iterator(); j.hasNext(); ) {
            ExamOwner xo = (ExamOwner) j.next();
            subject = xo.getCourse().getSubjectArea();
            dept = subject.getDepartment();
            break;
          }
          ChangeLog.addChange(
              hibSession,
              owner,
              exam.getSession(),
              exam,
              exam.getName()
                  + " ("
                  + oldAssignment.getPeriodAbbreviation()
                  + " "
                  + oldAssignment.getRoomsName(", ")
                  + " &rarr; N/A)",
              ChangeLog.Source.EXAM_SOLVER,
              ChangeLog.Operation.UNASSIGN,
              subject,
              dept);
        }
        continue;
      }
      exam.setAssignedPeriod(period);
      for (Iterator j = placement.getRoomPlacements().iterator(); j.hasNext(); ) {
        ExamRoomPlacement room = (ExamRoomPlacement) j.next();
        Location location = new LocationDAO().get(room.getId());
        if (location == null) {
          iProgress.warn("Location " + room.getName() + " (id:" + room.getId() + ") not found.");
          continue;
        }
        exam.getAssignedRooms().add(location);
      }
      exam.setAssignedPreference(
          new ExamAssignment(placement, getAssignment()).getAssignedPreferenceString());

      hibSession.saveOrUpdate(exam);
      ExamAssignment newAssignment = new ExamAssignment(exam);
      if (!ToolBox.equals(newAssignment.getPeriodId(), oldAssignment.getPeriodId())
          || !ToolBox.equals(newAssignment.getRooms(), oldAssignment.getRooms())) {
        SubjectArea subject = null;
        Department dept = null;
        for (Iterator j = new TreeSet(exam.getOwners()).iterator(); j.hasNext(); ) {
          ExamOwner xo = (ExamOwner) j.next();
          subject = xo.getCourse().getSubjectArea();
          dept = subject.getDepartment();
          break;
        }
        ChangeLog.addChange(
            hibSession,
            owner,
            exam.getSession(),
            exam,
            exam.getName()
                + " ("
                + (oldAssignment.getPeriod() == null
                    ? "N/A"
                    : oldAssignment.getPeriodAbbreviation()
                        + " "
                        + oldAssignment.getRoomsName(", "))
                + " &rarr; "
                + newAssignment.getPeriodAbbreviation()
                + " "
                + newAssignment.getRoomsName(", ")
                + ")",
            ChangeLog.Source.EXAM_SOLVER,
            ChangeLog.Operation.ASSIGN,
            subject,
            dept);
      }
    }
    iProgress.setPhase("Saving conflicts...", getAssignment().nrAssignedVariables());
    for (Exam examVar : getAssignment().assignedVariables()) {
      iProgress.incProgress();
      org.unitime.timetable.model.Exam exam =
          (org.unitime.timetable.model.Exam) examTable.get(examVar.getId());
      if (exam == null) continue;
      ExamPlacement placement = (ExamPlacement) getAssignment().getValue(examVar);
      ExamAssignmentInfo info = new ExamAssignmentInfo(placement, getAssignment());
      for (Iterator i = info.getDirectConflicts().iterator(); i.hasNext(); ) {
        ExamAssignmentInfo.DirectConflict dc = (ExamAssignmentInfo.DirectConflict) i.next();
        if (dc.getOtherExam() == null) continue;
        if (examVar.getId() < dc.getOtherExam().getExamId().longValue()) {
          org.unitime.timetable.model.Exam otherExam =
              (org.unitime.timetable.model.Exam) examTable.get(dc.getOtherExam().getExamId());
          if (otherExam == null) {
            iProgress.warn(
                "Exam "
                    + dc.getOtherExam().getExamName()
                    + " (id:"
                    + dc.getOtherExam().getExamId()
                    + ") not found.");
            continue;
          }
          ExamConflict conf = new ExamConflict();
          conf.setConflictType(ExamConflict.sConflictTypeDirect);
          conf.setStudents(getStudents(hibSession, dc.getStudents()));
          conf.setNrStudents(conf.getStudents().size());
          hibSession.save(conf);
          exam.getConflicts().add(conf);
          otherExam.getConflicts().add(conf);
          iProgress.debug(
              "Direct conflict of "
                  + dc.getStudents().size()
                  + " students between "
                  + exam.getLabel()
                  + " and "
                  + otherExam.getLabel());
        }
      }
      for (Iterator i = info.getBackToBackConflicts().iterator(); i.hasNext(); ) {
        ExamAssignmentInfo.BackToBackConflict btb =
            (ExamAssignmentInfo.BackToBackConflict) i.next();
        if (examVar.getId() < btb.getOtherExam().getExamId().longValue()) {
          org.unitime.timetable.model.Exam otherExam =
              (org.unitime.timetable.model.Exam) examTable.get(btb.getOtherExam().getExamId());
          if (otherExam == null) {
            iProgress.warn(
                "Exam "
                    + btb.getOtherExam().getExamName()
                    + " (id:"
                    + btb.getOtherExam().getExamId()
                    + ") not found.");
            continue;
          }
          ExamConflict conf = new ExamConflict();
          conf.setConflictType(
              btb.isDistance()
                  ? ExamConflict.sConflictTypeBackToBackDist
                  : ExamConflict.sConflictTypeBackToBack);
          conf.setDistance(btb.getDistance());
          conf.setStudents(getStudents(hibSession, btb.getStudents()));
          conf.setNrStudents(conf.getStudents().size());
          exam.getConflicts().add(conf);
          otherExam.getConflicts().add(conf);
          hibSession.save(conf);
          iProgress.debug(
              "Back-to-back conflict of "
                  + btb.getStudents().size()
                  + " students between "
                  + exam.getLabel()
                  + " and "
                  + otherExam.getLabel());
        }
      }
      m2d:
      for (Iterator i = info.getMoreThanTwoADaysConflicts().iterator(); i.hasNext(); ) {
        ExamAssignmentInfo.MoreThanTwoADayConflict m2d =
            (ExamAssignmentInfo.MoreThanTwoADayConflict) i.next();
        HashSet confExams = new HashSet();
        confExams.add(exam);
        for (Iterator j = m2d.getOtherExams().iterator(); j.hasNext(); ) {
          ExamAssignment otherExamAsg = (ExamAssignment) j.next();
          if (examVar.getId() >= otherExamAsg.getExamId().longValue()) continue m2d;
          org.unitime.timetable.model.Exam otherExam =
              (org.unitime.timetable.model.Exam) examTable.get(otherExamAsg.getExamId());
          if (otherExam == null) {
            iProgress.warn(
                "Exam "
                    + otherExamAsg.getExamName()
                    + " (id:"
                    + otherExamAsg.getExamId()
                    + ") not found.");
            continue;
          }
          confExams.add(otherExam);
        }
        if (confExams.size() >= 3) {
          ExamConflict conf = new ExamConflict();
          conf.setConflictType(ExamConflict.sConflictTypeMoreThanTwoADay);
          conf.setStudents(getStudents(hibSession, m2d.getStudents()));
          conf.setNrStudents(conf.getStudents().size());
          hibSession.save(conf);
          for (Iterator j = confExams.iterator(); j.hasNext(); )
            ((org.unitime.timetable.model.Exam) j.next()).getConflicts().add(conf);
          iProgress.debug(
              "More than 2 a day conflict of "
                  + m2d.getStudents().size()
                  + " students between "
                  + exam.getLabel()
                  + " and "
                  + m2d.getOtherExams());
        }
      }

      for (Iterator i = info.getInstructorDirectConflicts().iterator(); i.hasNext(); ) {
        ExamAssignmentInfo.DirectConflict dc = (ExamAssignmentInfo.DirectConflict) i.next();
        if (dc.getOtherExam() == null) continue;
        if (examVar.getId() < dc.getOtherExam().getExamId().longValue()) {
          org.unitime.timetable.model.Exam otherExam =
              (org.unitime.timetable.model.Exam) examTable.get(dc.getOtherExam().getExamId());
          if (otherExam == null) {
            iProgress.warn(
                "Exam "
                    + dc.getOtherExam().getExamName()
                    + " (id:"
                    + dc.getOtherExam().getExamId()
                    + ") not found.");
            continue;
          }
          ExamConflict conf = new ExamConflict();
          conf.setConflictType(ExamConflict.sConflictTypeDirect);
          conf.setInstructors(getInstructors(hibSession, dc.getStudents()));
          conf.setNrInstructors(conf.getInstructors().size());
          hibSession.save(conf);
          exam.getConflicts().add(conf);
          otherExam.getConflicts().add(conf);
          iProgress.debug(
              "Direct conflict of "
                  + dc.getStudents().size()
                  + " instructors between "
                  + exam.getLabel()
                  + " and "
                  + otherExam.getLabel());
        }
      }
      for (Iterator i = info.getInstructorBackToBackConflicts().iterator(); i.hasNext(); ) {
        ExamAssignmentInfo.BackToBackConflict btb =
            (ExamAssignmentInfo.BackToBackConflict) i.next();
        if (examVar.getId() < btb.getOtherExam().getExamId().longValue()) {
          org.unitime.timetable.model.Exam otherExam =
              (org.unitime.timetable.model.Exam) examTable.get(btb.getOtherExam().getExamId());
          if (otherExam == null) {
            iProgress.warn(
                "Exam "
                    + btb.getOtherExam().getExamName()
                    + " (id:"
                    + btb.getOtherExam().getExamId()
                    + ") not found.");
            continue;
          }
          ExamConflict conf = new ExamConflict();
          conf.setConflictType(
              btb.isDistance()
                  ? ExamConflict.sConflictTypeBackToBackDist
                  : ExamConflict.sConflictTypeBackToBack);
          conf.setDistance(btb.getDistance());
          conf.setInstructors(getInstructors(hibSession, btb.getStudents()));
          conf.setNrInstructors(conf.getInstructors().size());
          exam.getConflicts().add(conf);
          otherExam.getConflicts().add(conf);
          hibSession.save(conf);
          iProgress.debug(
              "Back-to-back conflict of "
                  + btb.getStudents().size()
                  + " instructors between "
                  + exam.getLabel()
                  + " and "
                  + otherExam.getLabel());
        }
      }
      m2d:
      for (Iterator i = info.getInstructorMoreThanTwoADaysConflicts().iterator(); i.hasNext(); ) {
        ExamAssignmentInfo.MoreThanTwoADayConflict m2d =
            (ExamAssignmentInfo.MoreThanTwoADayConflict) i.next();
        HashSet confExams = new HashSet();
        confExams.add(exam);
        for (Iterator j = m2d.getOtherExams().iterator(); j.hasNext(); ) {
          ExamAssignment otherExamAsg = (ExamAssignment) j.next();
          if (examVar.getId() >= otherExamAsg.getExamId().longValue()) continue m2d;
          org.unitime.timetable.model.Exam otherExam =
              (org.unitime.timetable.model.Exam) examTable.get(otherExamAsg.getExamId());
          if (otherExam == null) {
            iProgress.warn(
                "Exam "
                    + otherExamAsg.getExamName()
                    + " (id:"
                    + otherExamAsg.getExamId()
                    + ") not found.");
            continue;
          }
          confExams.add(otherExam);
        }
        if (confExams.size() >= 3) {
          ExamConflict conf = new ExamConflict();
          conf.setConflictType(ExamConflict.sConflictTypeMoreThanTwoADay);
          conf.setInstructors(getInstructors(hibSession, m2d.getStudents()));
          conf.setNrInstructors(conf.getInstructors().size());
          hibSession.save(conf);
          for (Iterator j = confExams.iterator(); j.hasNext(); )
            ((org.unitime.timetable.model.Exam) j.next()).getConflicts().add(conf);
          iProgress.debug(
              "More than 2 a day conflict of "
                  + m2d.getStudents().size()
                  + " instructors between "
                  + exam.getLabel()
                  + " and "
                  + m2d.getOtherExams());
        }
      }
    }
    iProgress.setPhase("Saving events...", getAssignment().nrAssignedVariables());
    String ownerPuid = getModel().getProperties().getProperty("General.OwnerPuid");
    EventContact contact = EventContact.findByExternalUniqueId(ownerPuid);
    if (contact == null) {
      TimetableManager manager = TimetableManager.findByExternalId(ownerPuid);
      contact = new EventContact();
      contact.setFirstName(manager.getFirstName());
      contact.setMiddleName(manager.getMiddleName());
      contact.setLastName(manager.getLastName());
      contact.setExternalUniqueId(manager.getExternalUniqueId());
      contact.setEmailAddress(manager.getEmailAddress());
      hibSession.save(contact);
    }
    for (Exam examVar : getAssignment().assignedVariables()) {
      iProgress.incProgress();
      org.unitime.timetable.model.Exam exam =
          (org.unitime.timetable.model.Exam) examTable.get(examVar.getId());
      if (exam == null) continue;
      ExamEvent event = exam.generateEvent(null, true);
      if (event != null) {
        event.setEventName(examVar.getName());
        event.setMinCapacity(examVar.getSize());
        event.setMaxCapacity(examVar.getSize());
        event.setMainContact(contact);
        hibSession.saveOrUpdate(event);
      }
      if (event != null || !exam.getConflicts().isEmpty()) hibSession.saveOrUpdate(exam);
    }
  }
  @Override
  public SaveOrApproveEventRpcResponse execute(SaveEventRpcRequest request, EventContext context) {
    if (request.getEvent().hasContact()
        && (request.getEvent().getContact().getExternalId() == null
            || !request
                .getEvent()
                .getContact()
                .getExternalId()
                .equals(context.getUser().getExternalUserId()))) {
      switch (request.getEvent().getType()) {
        case Special:
        case Course:
        case Unavailabile:
          context.checkPermission(Right.EventLookupContact);
      }
    }
    if (request.getEvent().getId() == null) { // new even
      switch (request.getEvent().getType()) {
        case Special:
          context.checkPermission(Right.EventAddSpecial);
          break;
        case Course:
          context.checkPermission(Right.EventAddCourseRelated);
          break;
        case Unavailabile:
          context.checkPermission(Right.EventAddUnavailable);
          break;
        default:
          throw context.getException();
      }
    } else { // existing event
      context.checkPermission(request.getEvent().getId(), "Event", Right.EventEdit);
    }

    // Check main contact email
    if (request.getEvent().hasContact() && request.getEvent().getContact().hasEmail()) {
      try {
        new InternetAddress(request.getEvent().getContact().getEmail(), true);
      } catch (AddressException e) {
        throw new GwtRpcException(
            MESSAGES.badEmailAddress(request.getEvent().getContact().getEmail(), e.getMessage()));
      }
    }
    // Check additional emails
    if (request.getEvent().hasEmail()) {
      String suffix = ApplicationProperty.EmailDefaultAddressSuffix.value();
      for (String address : request.getEvent().getEmail().split("[\n,]")) {
        String email = address.trim();
        if (email.isEmpty()) continue;
        if (suffix != null && email.indexOf('@') < 0) email += suffix;
        try {
          new InternetAddress(email, true);
        } catch (AddressException e) {
          throw new GwtRpcException(MESSAGES.badEmailAddress(address, e.getMessage()));
        }
      }
    }

    org.hibernate.Session hibSession = SessionDAO.getInstance().getSession();
    Transaction tx = hibSession.beginTransaction();
    try {
      Session session = SessionDAO.getInstance().get(request.getSessionId(), hibSession);
      Date now = new Date();

      Event event = null;
      if (request.getEvent().getId() != null) {
        event = EventDAO.getInstance().get(request.getEvent().getId(), hibSession);
      } else {
        switch (request.getEvent().getType()) {
          case Special:
            event = new SpecialEvent();
            break;
          case Course:
            event = new CourseEvent();
            break;
          case Unavailabile:
            event = new UnavailableEvent();
            break;
          default:
            throw new GwtRpcException(
                MESSAGES.failedSaveEventWrongType(request.getEvent().getType().getName(CONSTANTS)));
        }
      }

      SaveOrApproveEventRpcResponse response = new SaveOrApproveEventRpcResponse();

      event.setEventName(request.getEvent().getName());
      if (event.getEventName() == null
          || event.getEventName().isEmpty()
              && request.getEvent().getType() == EventType.Unavailabile)
        event.setEventName(MESSAGES.unavailableEventDefaultName());
      event.setEmail(request.getEvent().getEmail());
      if (context.hasPermission(Right.EventSetExpiration) || event.getExpirationDate() != null)
        event.setExpirationDate(request.getEvent().getExpirationDate());
      event.setSponsoringOrganization(
          request.getEvent().hasSponsor()
              ? SponsoringOrganizationDAO.getInstance()
                  .get(request.getEvent().getSponsor().getUniqueId())
              : null);
      if (event instanceof UnavailableEvent) {
      } else if (event instanceof SpecialEvent) {
        event.setMinCapacity(request.getEvent().getMaxCapacity());
        event.setMaxCapacity(request.getEvent().getMaxCapacity());
      }
      if (event.getAdditionalContacts() == null) {
        event.setAdditionalContacts(new HashSet<EventContact>());
      }
      if (context.hasPermission(Right.EventLookupContact)) {
        Set<EventContact> existingContacts =
            new HashSet<EventContact>(event.getAdditionalContacts());
        event.getAdditionalContacts().clear();
        if (request.getEvent().hasAdditionalContacts())
          for (ContactInterface c : request.getEvent().getAdditionalContacts()) {
            if (c.getExternalId() == null) continue;
            EventContact contact = null;
            for (EventContact x : existingContacts)
              if (c.getExternalId().equals(x.getExternalUniqueId())) {
                contact = x;
                break;
              }
            if (contact == null) {
              contact =
                  (EventContact)
                      hibSession
                          .createQuery("from EventContact where externalUniqueId = :externalId")
                          .setString("externalId", c.getExternalId())
                          .setMaxResults(1)
                          .uniqueResult();
            }
            if (contact == null) {
              contact = new EventContact();
              contact.setExternalUniqueId(c.getExternalId());
              contact.setFirstName(c.getFirstName());
              contact.setMiddleName(c.getMiddleName());
              contact.setLastName(c.getLastName());
              contact.setAcademicTitle(c.getAcademicTitle());
              contact.setEmailAddress(c.getEmail());
              contact.setPhone(c.getPhone());
              hibSession.save(contact);
            }
            event.getAdditionalContacts().add(contact);
          }
      }

      EventContact main = event.getMainContact();
      if (main == null
          || main.getExternalUniqueId() == null
          || !main.getExternalUniqueId().equals(request.getEvent().getContact().getExternalId())) {
        main =
            (EventContact)
                hibSession
                    .createQuery("from EventContact where externalUniqueId = :externalId")
                    .setString("externalId", request.getEvent().getContact().getExternalId())
                    .setMaxResults(1)
                    .uniqueResult();
        if (main == null) {
          main = new EventContact();
          main.setExternalUniqueId(request.getEvent().getContact().getExternalId());
        }
      }
      main.setFirstName(request.getEvent().getContact().getFirstName());
      main.setMiddleName(request.getEvent().getContact().getMiddleName());
      main.setLastName(request.getEvent().getContact().getLastName());
      main.setAcademicTitle(request.getEvent().getContact().getAcademicTitle());
      main.setEmailAddress(request.getEvent().getContact().getEmail());
      main.setPhone(request.getEvent().getContact().getPhone());
      hibSession.saveOrUpdate(main);
      event.setMainContact(main);

      if (event.getNotes() == null) event.setNotes(new HashSet<EventNote>());

      if (event.getMeetings() == null) event.setMeetings(new HashSet<Meeting>());
      Set<Meeting> remove = new HashSet<Meeting>(event.getMeetings());
      TreeSet<Meeting> createdMeetings = new TreeSet<Meeting>();
      Set<Meeting> cancelledMeetings = new TreeSet<Meeting>();
      Set<Meeting> updatedMeetings = new TreeSet<Meeting>();
      for (MeetingInterface m : request.getEvent().getMeetings()) {
        Meeting meeting = null;
        if (m.getApprovalStatus() == ApprovalStatus.Deleted) {
          if (!context.hasPermission(meeting, Right.EventMeetingDelete)
              && context.hasPermission(meeting, Right.EventMeetingCancel)) {
            // Cannot delete, but can cancel --> cancel the meeting instead
            m.setApprovalStatus(ApprovalStatus.Cancelled);
          } else {
            continue;
          }
        }
        if (m.getId() != null)
          for (Iterator<Meeting> i = remove.iterator(); i.hasNext(); ) {
            Meeting x = i.next();
            if (m.getId().equals(x.getUniqueId())) {
              meeting = x;
              i.remove();
              break;
            }
          }
        if (meeting != null) {
          if (m.getApprovalStatus().ordinal() != meeting.getApprovalStatus()) {
            switch (m.getApprovalStatus()) {
              case Cancelled:
                switch (meeting.getEvent().getEventType()) {
                  case Event.sEventTypeFinalExam:
                  case Event.sEventTypeMidtermExam:
                    if (!context.hasPermission(meeting, Right.EventMeetingCancelExam))
                      throw new GwtRpcException(
                          MESSAGES.failedApproveEventNoRightsToCancel(toString(meeting)));
                    break;
                  case Event.sEventTypeClass:
                    if (!context.hasPermission(meeting, Right.EventMeetingCancelClass))
                      throw new GwtRpcException(
                          MESSAGES.failedApproveEventNoRightsToCancel(toString(meeting)));
                    break;
                  default:
                    if (!context.hasPermission(meeting, Right.EventMeetingCancel))
                      throw new GwtRpcException(
                          MESSAGES.failedApproveEventNoRightsToCancel(toString(meeting)));
                    break;
                }
                meeting.setStatus(Meeting.Status.CANCELLED);
                meeting.setApprovalDate(now);
                hibSession.update(meeting);
                cancelledMeetings.add(meeting);
                response.addCancelledMeeting(m);
            }
          } else {
            if (m.getStartOffset()
                    != (meeting.getStartOffset() == null ? 0 : meeting.getStartOffset())
                || m.getEndOffset()
                    != (meeting.getStopOffset() == null ? 0 : meeting.getStopOffset())) {
              if (!context.hasPermission(meeting, Right.EventMeetingEdit))
                throw new GwtRpcException(
                    MESSAGES.failedSaveEventCanNotEditMeeting(toString(meeting)));
              meeting.setStartOffset(m.getStartOffset());
              meeting.setStopOffset(m.getEndOffset());
              hibSession.update(meeting);
              response.addUpdatedMeeting(m);
              updatedMeetings.add(meeting);
            }
          }
        } else {
          response.addCreatedMeeting(m);
          meeting = new Meeting();
          meeting.setEvent(event);
          Location location = null;
          if (m.hasLocation()) {
            if (m.getLocation().getId() != null)
              location = LocationDAO.getInstance().get(m.getLocation().getId(), hibSession);
            else if (m.getLocation().getName() != null)
              location =
                  Location.findByName(
                      hibSession, request.getSessionId(), m.getLocation().getName());
          }
          if (location == null)
            throw new GwtRpcException(MESSAGES.failedSaveEventNoLocation(toString(m)));
          meeting.setLocationPermanentId(location.getPermanentId());
          meeting.setStatus(Meeting.Status.PENDING);
          meeting.setApprovalDate(null);
          if (!context.hasPermission(location, Right.EventLocation))
            throw new GwtRpcException(MESSAGES.failedSaveEventWrongLocation(m.getLocationName()));
          if (request.getEvent().getType() == EventType.Unavailabile
              && !context.hasPermission(location, Right.EventLocationUnavailable))
            throw new GwtRpcException(
                MESSAGES.failedSaveCannotMakeUnavailable(m.getLocationName()));
          if (m.getApprovalStatus() == ApprovalStatus.Approved
              && context.hasPermission(location, Right.EventLocationApprove)) {
            meeting.setStatus(Meeting.Status.APPROVED);
            meeting.setApprovalDate(now);
          }
          if (context.isPastOrOutside(m.getMeetingDate()))
            throw new GwtRpcException(
                MESSAGES.failedSaveEventPastOrOutside(getDateFormat().format(m.getMeetingDate())));
          if (!context.hasPermission(location, Right.EventLocationOverbook)) {
            List<MeetingConflictInterface> conflicts =
                computeConflicts(hibSession, m, event.getUniqueId());
            if (!conflicts.isEmpty())
              throw new GwtRpcException(
                  MESSAGES.failedSaveEventConflict(toString(m), toString(conflicts.get(0))));
          }
          m.setApprovalDate(meeting.getApprovalDate());
          m.setApprovalStatus(meeting.getApprovalStatus());
          meeting.setStartPeriod(m.getStartSlot());
          meeting.setStopPeriod(m.getEndSlot());
          meeting.setStartOffset(m.getStartOffset());
          meeting.setStopOffset(m.getEndOffset());
          meeting.setClassCanOverride(true);
          meeting.setMeetingDate(m.getMeetingDate());
          event.getMeetings().add(meeting);
          createdMeetings.add(meeting);
        }
        // automatic approval
        if (meeting.getApprovalDate() == null) {
          switch (request.getEvent().getType()) {
            case Unavailabile:
            case Class:
            case FinalExam:
            case MidtermExam:
              meeting.setStatus(Meeting.Status.APPROVED);
              meeting.setApprovalDate(now);
              break;
          }
        }
      }

      if (!remove.isEmpty()) {
        for (Iterator<Meeting> i = remove.iterator(); i.hasNext(); ) {
          Meeting m = i.next();
          if (!context.hasPermission(m, Right.EventMeetingDelete)) {
            if (m.getStatus() == Status.CANCELLED || m.getStatus() == Status.REJECTED) {
              i.remove();
              continue;
            }
            throw new GwtRpcException(MESSAGES.failedSaveEventCanNotDeleteMeeting(toString(m)));
          }
          MeetingInterface meeting = new MeetingInterface();
          meeting.setId(m.getUniqueId());
          meeting.setMeetingDate(m.getMeetingDate());
          meeting.setDayOfWeek(Constants.getDayOfWeek(m.getMeetingDate()));
          meeting.setStartTime(m.getStartTime().getTime());
          meeting.setStopTime(m.getStopTime().getTime());
          meeting.setDayOfYear(
              CalendarUtils.date2dayOfYear(session.getSessionStartYear(), m.getMeetingDate()));
          meeting.setStartSlot(m.getStartPeriod());
          meeting.setEndSlot(m.getStopPeriod());
          meeting.setStartOffset(m.getStartOffset() == null ? 0 : m.getStartOffset());
          meeting.setEndOffset(m.getStopOffset() == null ? 0 : m.getStopOffset());
          meeting.setPast(context.isPastOrOutside(m.getStartTime()));
          meeting.setApprovalDate(m.getApprovalDate());
          meeting.setApprovalStatus(m.getApprovalStatus());
          if (m.getLocation() != null) {
            ResourceInterface location = new ResourceInterface();
            location.setType(ResourceType.ROOM);
            location.setId(m.getLocation().getUniqueId());
            location.setName(m.getLocation().getLabel());
            location.setSize(m.getLocation().getCapacity());
            location.setRoomType(m.getLocation().getRoomTypeLabel());
            location.setBreakTime(m.getLocation().getEffectiveBreakTime());
            location.setMessage(m.getLocation().getEventMessage());
            location.setIgnoreRoomCheck(m.getLocation().isIgnoreRoomCheck());
            meeting.setLocation(location);
          }
          response.addDeletedMeeting(meeting);
        }
        event.getMeetings().removeAll(remove);
      }

      EventInterface.DateFormatter df =
          new EventInterface.DateFormatter() {
            Formats.Format<Date> dfShort = Formats.getDateFormat(Formats.Pattern.DATE_EVENT_SHORT);
            Formats.Format<Date> dfLong = Formats.getDateFormat(Formats.Pattern.DATE_EVENT_LONG);

            @Override
            public String formatFirstDate(Date date) {
              return dfShort.format(date);
            }

            @Override
            public String formatLastDate(Date date) {
              return dfLong.format(date);
            }
          };

      FileItem attachment = (FileItem) context.getAttribute(UploadServlet.SESSION_LAST_FILE);
      boolean attached = false;
      if (response.hasCreatedMeetings()) {
        EventNote note = new EventNote();
        note.setEvent(event);
        note.setNoteType(
            event.getUniqueId() == null
                ? EventNote.sEventNoteTypeCreateEvent
                : EventNote.sEventNoteTypeAddMeetings);
        note.setTimeStamp(now);
        note.setUser(context.getUser().getTrueName());
        note.setUserId(context.getUser().getTrueExternalUserId());
        if (request.hasMessage()) note.setTextNote(request.getMessage());
        note.setMeetings(
            EventInterface.toString(response.getCreatedMeetings(), CONSTANTS, "\n", df));
        note.setAffectedMeetings(createdMeetings);
        event.getNotes().add(note);
        NoteInterface n = new NoteInterface();
        n.setDate(now);
        n.setMeetings(note.getMeetings());
        n.setUser(context.getUser().getTrueName());
        n.setType(NoteInterface.NoteType.values()[note.getNoteType()]);
        n.setNote(note.getTextNote());
        if (attachment != null) {
          note.setAttachedName(attachment.getName());
          note.setAttachedFile(attachment.get());
          note.setAttachedContentType(attachment.getContentType());
          attached = true;
          n.setAttachment(attachment.getName());
        }
        response.addNote(n);
      }
      if (response.hasUpdatedMeetings()
          || (!response.hasCreatedMeetings()
              && !response.hasDeletedMeetings()
              && !response.hasCancelledMeetings())) {
        EventNote note = new EventNote();
        note.setEvent(event);
        note.setNoteType(EventNote.sEventNoteTypeEditEvent);
        note.setTimeStamp(now);
        note.setUser(context.getUser().getTrueName());
        note.setUserId(context.getUser().getTrueExternalUserId());
        note.setAffectedMeetings(updatedMeetings);
        if (request.hasMessage()) note.setTextNote(request.getMessage());
        if (response.hasUpdatedMeetings())
          note.setMeetings(
              EventInterface.toString(response.getUpdatedMeetings(), CONSTANTS, "\n", df));
        event.getNotes().add(note);
        NoteInterface n = new NoteInterface();
        n.setDate(now);
        n.setMeetings(note.getMeetings());
        n.setUser(context.getUser().getTrueName());
        n.setType(NoteInterface.NoteType.values()[note.getNoteType()]);
        n.setNote(note.getTextNote());
        if (attachment != null && !attached) {
          note.setAttachedName(attachment.getName());
          note.setAttachedFile(attachment.get());
          note.setAttachedContentType(attachment.getContentType());
          attached = true;
          n.setAttachment(attachment.getName());
        }
        response.addNote(n);
      }
      if (response.hasDeletedMeetings()) {
        EventNote note = new EventNote();
        note.setEvent(event);
        note.setNoteType(EventNote.sEventNoteTypeDeletion);
        note.setTimeStamp(now);
        note.setUser(context.getUser().getTrueName());
        note.setUserId(context.getUser().getTrueExternalUserId());
        if (request.hasMessage()) note.setTextNote(request.getMessage());
        note.setMeetings(
            EventInterface.toString(response.getDeletedMeetings(), CONSTANTS, "\n", df));
        event.getNotes().add(note);
        NoteInterface n = new NoteInterface();
        n.setDate(now);
        n.setMeetings(note.getMeetings());
        n.setUser(context.getUser().getTrueName());
        n.setType(NoteInterface.NoteType.values()[note.getNoteType()]);
        n.setNote(note.getTextNote());
        if (attachment != null && !attached) {
          note.setAttachedName(attachment.getName());
          note.setAttachedFile(attachment.get());
          note.setAttachedContentType(attachment.getContentType());
          attached = true;
          n.setAttachment(attachment.getName());
        }
        response.addNote(n);
      }
      if (response.hasCancelledMeetings()) {
        EventNote note = new EventNote();
        note.setEvent(event);
        note.setNoteType(EventNote.sEventNoteTypeCancel);
        note.setTimeStamp(now);
        note.setUser(context.getUser().getTrueName());
        note.setUserId(context.getUser().getTrueExternalUserId());
        note.setAffectedMeetings(cancelledMeetings);
        if (request.hasMessage()) note.setTextNote(request.getMessage());
        note.setMeetings(
            EventInterface.toString(response.getCancelledMeetings(), CONSTANTS, "\n", df));
        event.getNotes().add(note);
        NoteInterface n = new NoteInterface();
        n.setDate(now);
        n.setMeetings(note.getMeetings());
        n.setUser(context.getUser().getTrueName());
        n.setType(NoteInterface.NoteType.values()[note.getNoteType()]);
        n.setNote(note.getTextNote());
        if (attachment != null && !attached) {
          note.setAttachedName(attachment.getName());
          note.setAttachedFile(attachment.get());
          note.setAttachedContentType(attachment.getContentType());
          attached = true;
          n.setAttachment(attachment.getName());
        }
        response.addNote(n);
      }

      if (request.getEvent().getType() == EventType.Course) {
        CourseEvent ce = (CourseEvent) event;
        ce.setReqAttendance(request.getEvent().hasRequiredAttendance());
        if (ce.getRelatedCourses() == null) ce.setRelatedCourses(new HashSet<RelatedCourseInfo>());
        else ce.getRelatedCourses().clear();
        if (request.getEvent().hasRelatedObjects())
          for (RelatedObjectInterface r : request.getEvent().getRelatedObjects()) {
            RelatedCourseInfo related = new RelatedCourseInfo();
            related.setEvent(ce);
            if (r.getSelection() != null) {
              related.setOwnerId(r.getUniqueId());
              related.setOwnerType(r.getType().ordinal());
              related.setCourse(
                  CourseOfferingDAO.getInstance().get(r.getSelection()[1], hibSession));
            } else {
              switch (r.getType()) {
                case Course:
                  related.setOwner(CourseOfferingDAO.getInstance().get(r.getUniqueId()));
                  break;
                case Class:
                  related.setOwner(Class_DAO.getInstance().get(r.getUniqueId()));
                  break;
                case Config:
                  related.setOwner(InstrOfferingConfigDAO.getInstance().get(r.getUniqueId()));
                  break;
                case Offering:
                  related.setOwner(InstructionalOfferingDAO.getInstance().get(r.getUniqueId()));
                  break;
              }
            }
            ce.getRelatedCourses().add(related);
          }
      }

      if (event.getUniqueId() == null) {
        hibSession.save(event);
        response.setEvent(
            EventDetailBackend.getEventDetail(
                SessionDAO.getInstance().get(request.getSessionId(), hibSession), event, context));
      } else if (event.getMeetings().isEmpty()) {
        response.setEvent(
            EventDetailBackend.getEventDetail(
                SessionDAO.getInstance().get(request.getSessionId(), hibSession), event, context));
        response.getEvent().setId(null);
        hibSession.delete(event);
      } else {
        hibSession.update(event);
        response.setEvent(
            EventDetailBackend.getEventDetail(
                SessionDAO.getInstance().get(request.getSessionId(), hibSession), event, context));
      }

      tx.commit();

      new EventEmail(request, response).send(context);

      return response;
    } catch (Exception ex) {
      tx.rollback();
      if (ex instanceof GwtRpcException) throw (GwtRpcException) ex;
      throw new GwtRpcException(ex.getMessage(), ex);
    }
  }