code: static Set<User> brokeUserList(final String dataFilePath)
      {
          Set<User> users = new HashSet<User>();
          Workbook workBook = null;
          File file = new File(dataFilePath);
          InputStream excelDocumentStream = null;
          try
          {
              excelDocumentStream = new FileInputStream(file);
              POIFSFileSystem fsPOI = new POIFSFileSystem(new BufferedInputStream(excelDocumentStream));
              workBook = new HSSFWorkbook(fsPOI);
              UserBroker parser = new UserBroker(workBook.getSheetAt(0));
              User user;
              while ((user = parser.addUser(users)) != null)
              {
                  users.add(user);
              }
              excelDocumentStream.close();
  
          }
          catch (Exception e)
          {
            throw new RuntimeException("Error while processing brokeUserList(), Caused by :",e);
          }
          
          return users;
      }
docs: Reads and populate a collection of {@link User} from excel file available at dataFilePath.
  
  @param dataFilePath
  @return  collection of users.