<s:select/> 标签的默认值有关问题

<s:select/> 标签的默认值问题
<s:select name="aa" list="sfcOperationList" listKey="id" listValue="opName" headerKey="%{sfcProutingDetail.sfcOperation.id}"
headerValue="%{sfcProutingDetail.sfcOperation.opName}" label="工序"/>

sfcOperationList 迭代集合
sfcProutingDetail.sfcOperation.opName 默认值