私有方法五

 /**
     * @author : lKF35745
     * @version: 1.0
     * <p>时间 : 2011-1-6</p>
     * <p>描述 : 根据与会者ID查询出自己所在的会议</p>
     * <p>Copyright 1988-2005, Huawei Tech. Co., Ltd.</p>
     * @param  ParticipantID 与会者编号
     * @return ConferenceID 子会议编号 
     */
    private String getConferenceIdByPartId(final ParticipantID participantID)
    {
        if (logger.isDebugEnabled())
        {
            logger.debug("begin getSubConferenceIDByParticipantID and param: "
                    + participantID);
        }
        
        if (null == participantID)
        {
            logger.warn("ParticipantID is null ");
            return null;
        }
        
        //根据与会者编号找到与会者信息类
        ParticipantInfo participantInfo = Activator.getConferenceService()
                .getParticipantInfo(participantID);
        
        if (null == participantInfo)
        {
            logger.warn("get ParticipantInfo Object is null.");
            return null;
        }
        //得到会议编号
        String conferenceID = participantInfo.getConferenceID().getId();
        
        if (null == conferenceID)
        {
            logger.warn("get conferenceID is null.");
            return null;
        }
        
        if (logger.isDebugEnabled())
        {
            logger
                    .debug("end beagin getSubConferenceIDByParticipantID conferenceID value is "
                            + conferenceID);
        }
        return conferenceID;
    }