STRUTS2 嵌套循环

<!--begin 类目循环 -->
<s:iterator value="categories" id='i' begin="0" step="1" status="status">

<s:if test="#i.parentId != #flag">
<s:set name="flag" value="#i.parentId" />

<tr>
<!--begin 一级类目 -->

<td><s:property value="#status.count"/></td>
<td>
<div class="input-group item-wrap" data="item-1">
<input class="form-control" type="text" value="${parentName}">
<input class="form-control" type="hidden" value="${parentId}">
<span class="input-group-addon btn"><i class="fa fa-times"></i></span>
</div>
</td>

<!--end 一级类目 -->
<!--begin 二级类目 -->
<td>
<s:iterator value="categories" id='id'>
<s:if test="#id.parentId == #flag">
<div class="clearfix mb-5 item-wrap"><div class="col-xs-7 input-group">
<input class="form-control" type="text" value="${childName}">
<input class="form-control" type="hidden" value="${childId}">
<span class="input-group-addon btn"><i class="fa fa-times"></i></span></div>
<div class="col-md-5 text-muted">
<input class="form-control" type="text" value="${childNotes}"></div></div>
</s:if>
</s:iterator>

<div class="clearfix col-xs-1">
<a href="#" class="btn btn-xs green btn-add-itme2" title="新增二级类目"><i class="fa fa-plus"></i> 新增二级类目</a>
</div>
</td>
<!--end 二级类目 -->
</tr>
</s:if>
</s:iterator>