java使用ExchangeService读取会议邮件：报错

//ExchangeService版本
ExchangeService service = new ExchangeService(ExchangeVersion.Exchange2007_SP1);
//用户名、密码、域
ExchangeCredentials credentials = new WebCredentials("账号", "密码");
service.setCredentials(credentials);
//设置邮件服务器地址
service.setUrl(new URI("服务器地址"));

/* CalendarFolder calendar = null;
calendar = CalendarFolder.bind(service, WellKnownFolderName.Calendar);*/
//创建过滤器
/* Folder inbox = Folder.bind(service, WellKnownFolderName.Inbox);
//创建过滤器条件，查询10封邮件
ItemView view = new ItemView(10);
//读取所有邮件
FindItemsResults<Item> findResults = service.findItems(inbox.getId(), view);
SimpleDateFormat format=new SimpleDateFormat("yyyy-MM-dd hh��ss");
for (Item item : findResults.getItems()) {
EmailMessage message = EmailMessage.bind(service, item.getId());
//message.load();
System.out.println("发送人->"+message.getSender());
System.out.println("标题--->" + item.getSubject());
System.out.println("邮件ID->"+item.getId());
System.out.println("创建时间->"+format.format(item.getDateTimeCreated()));
System.out.println("发送时间->"+format.format(item.getDateTimeSent()));
//System.out.println();
//System.out.println(item.getMimeContent());

}*/

SimpleDateFormat format=new SimpleDateFormat("yyyy-MM-dd hh��ss");

Date sta=DateUtils.getBeginOfMonth(stat);
Date end=DateUtils.getEndOfMonth(endd);
System.out.println("开始日期-->"+format.format(sta));
System.out.println("结束日期-->"+format.format(end));

   CalendarFolder calendar = CalendarFolder.bind(service, WellKnownFolderName.Calendar, new PropertySet());
CalendarView cView = new CalendarView(sta, end);
cView.setPropertySet(new PropertySet(
       AppointmentSchema.Id,
       AppointmentSchema.Subject,
       AppointmentSchema.Start,
       AppointmentSchema.End,
       AppointmentSchema.Location, //会议地点
       AppointmentSchema.Organizer, //组织者
       AppointmentSchema.AppointmentType //会议类型
       //AppointmentSchema.RequiredAttendees, //参与者会报错
       //AppointmentSchema.SUMMARY,
       //AppointmentSchema.OptionalAttendees
       ));
FindItemsResults<Appointment> appointments = calendar.findAppointments(cView);
for (Appointment appointment2 : appointments.getItems()) {
   //appointment2.getId()
   System.out.println("ID---->"+appointment2.getId());
   System.out.println("主题 -->" + appointment2.getSubject());
System.out.println("开始时间 -->" +DateUtils.parseDate(appointment2.getStart()));
System.out.println("结束时间 -->" +DateUtils.parseDate(appointment2.getEnd()));
System.out.println("地点-->" +appointment2.getLocation());
System.out.println("类型-->" +appointment2.getAppointmentType());
System.out.println("组织者-->" +appointment2.getOrganizer().getName());
System.out.println();
//System.out.println("参会者-->" +appointment2.getRequiredAttendees());
//System.out.println("参与者-->"+appointment2.getOptionalAttendees());
//System.out.println("内容-->" +appointment2.getBody());
//EmailMessage message = EmailMessage.bind(service, appointment2.getId());
//message.load();
//System.out.println(message.getSender());
}
} catch (Exception e) {
               // TODO Auto-generated catch block
               e.printStackTrace();
               logger.info(e.getMessage());
           }