public boolean demoteLE(LearningElementDto le) throws UnknownHostException, Exception {
   boolean ok = false;
   LearningElement model = dao.getLE(le.getId());
   if (model != null) {
     model.setStatus(0);
     dao.demoteLE(model);
     ok = true;
   } else throw new Exception("LearningElement does not exist. ");
   return ok;
 }
 public List<LearningElementDto> searchLearningElements(String keyword)
     throws UnknownHostException {
   List<LearningElement> LOList;
   LOList = dao.searchLE(keyword);
   List<LearningElementDto> objects = new ArrayList<>();
   for (LearningElement model : LOList) {
     LearningElementDto dto = new LearningElementDto();
     dto.setId(model.getId());
     dto.setRating(model.getRating());
     dto.setTitle(model.getTitle());
     dto.setDescription(model.getDescription());
     dto.setSubject(model.getSubject());
     dto.setDownloads(model.getDownloads());
     dto.setUploadDate(model.getUploadDate());
     dto.setUploadedBy(model.getUploadedBy());
     dto.setComments(model.getComments());
     dto.setRev(model.getRev());
     dto.setStatus(model.getStatus());
     objects.add(dto);
   }
   return objects;
 }
 public LearningElementDto getSpecificLearningElement(String id) throws UnknownHostException {
   LearningElement leModel = dao.getSpecificLearningElement(id);
   LearningElementDto dto = new LearningElementDto();
   if (leModel != null) {
     dto.setId(leModel.getId());
     dto.setTitle(leModel.getTitle());
     dto.setDescription(leModel.getDescription());
     dto.setSubject(leModel.getSubject());
     dto.setUploadDate(leModel.getUploadDate());
     dto.setDownloads(leModel.getDownloads());
     dto.setRating(leModel.getRating());
     dto.setRev(leModel.getRev());
     dto.setStatus(leModel.getStatus());
     dto.setComments(leModel.getComments());
     dto.setUploadedBy(leModel.getUploadedBy());
     dto.setFilePath(leModel.getFilePath());
   }
   return dto;
 }
 public boolean reviewLE(LearningElementDto le) throws UnknownHostException {
   LearningElement obj = dao.getSpecificLearningElementById(le.getId());
   obj.setComments(le.getComments());
   obj.setRating(le.getRating());
   return dao.saveLE(obj);
 }