类6

  session.setAttribute("softwareList", softwareListTemp);
            session.setAttribute("softwareListTemp", null);
        }
        else if ("cancel".equals(flag))
        {
            //如果是当前选择结束后点击取消
            //清空softwareList_temp中的值，不返回任何值
            session.setAttribute("softwareListTemp", null);
        }