hibernate in 查询

StringBuffer buf = new StringBuffer();   if (!forObject) {    buf.append("select count(*) ");   }   buf.append("from Agent agent where 1=1 ");

            String gradeId = (String)conditions.get("gradeId");            if(gradeId != null && !gradeId.equals("") && gradeId != ""){             buf.append(" and agent.gradeId=").append(gradeId);            }   

               buf.append(" and agent.agentId in (:agentIds) ");

   Query query = sess.createQuery(buf.toString());      List ids = CommisionInfoDelegateExt.findAgentIdList(conditions);   System.out.println("ids.length=" + ids.size());   query.setParameterList("agentIds",     ids);





当ids长度为0(空记录)时,query.list()出错.没办法,现在在ids.add("-1"),塞入一条绝对不存在的记录id(绝对是不可能的)