私有方法二

 /**
     * @author : lKF35745
     * @version: 1.0
     * <p>时间 : 2011-1-11</p>
     * <p>描述 : 得到视频源和被选看视频源</p>
     * <p>Copyright 1988-2005, Huawei Tech. Co., Ltd.</p>
     * @param videoSelectionParam
     */
    public void getParticipantId(final VideoSelectionParam videoSelectionParam)
    {
        if (logger.isDebugEnabled())
        {
            logger.debug("begin to getParticipantId and param is "
                    + videoSelectionParam);
        }
        
        //得到InnerVideoSelectionParam集合对象
        List<InnerVideoSelectionParam> innerVoideoparams = videoSelectionParam
                .getParams();
        
        if (null == innerVoideoparams || innerVoideoparams.size() < 1)
        {
            logger.warn("videoSelectionParam getParams is null");
            return;
        }
        
        //遍历取出目标视频源/被选看的视频与会者ID
        for (int i = 0; i < innerVoideoparams.size(); i++)
        {
            InnerVideoSelectionParam innerVideoSelectionParam = innerVoideoparams
                    .get(i);
            
            //得到目标视频源与会者编号
            ParticipantID dstScreenID = innerVideoSelectionParam.getDstScreen();
            
            if (null != dstScreenID)
            {
                //设置目标视频源与会者编号
                setCascadeDstScreen(dstScreenID);
            }
            
            //得到所有被选看的信息
            ParticipantID srcScreenID = null;
            List<ParticipantID> partIdSrcScreen = innerVideoSelectionParam
                    .getSrcScreen();
            if (partIdSrcScreen.size() == 1)
            {
                srcScreenID = partIdSrcScreen.get(0);
            }
            
            if (null == srcScreenID)
            {
                logger.warn("the srcScreenID is null");
            }
            
            setCascadeSrcScreen(srcScreenID);
        }
        
        if (logger.isDebugEnabled())
        {
            logger.debug("end to getParticipantId and DstScreen Value is"
                    + getCascadeDstScreen() + " and SrcScreen Value is "
                    + getCascadeSrcScreen());
        }
    }