hql集合set的实现

 public String getOrderGongdanchaxunByWxyAndXm(  String xm) {
            String hql="SELECT wo FROM WxOrder wo,WxBnfuwuxiangmu fwxm WHERE 1=1  ";
            if (StringUtil.isNotEmpty(xm)&&!xm.equals("选择服务项目")) {         //服务项目
                hql += " AND fwxm.idwxFuwuxiangmus in elements(wo.wxBnfuwuxiangmus) AND 
                          fwxm.wxFuwuxiangmuName='"+xm+"' ";
            }
            hql += "  ORDER BY wo.idwxOrder DESC";
            return hql;
  }