如何在插入的页面中包含平铺定义属性

我有一块瓷砖-定义.xml有这些定义。。。

<definition name="masterLayout" path="/WEB-INF/tiles-layouts/globalLayout.jsp">
    <put name="pageTemplate" value="over-ride for each page" />
</definition>

<definition name="childLayout" extends="masterLayout">
    <put name="pageTemplate" value="/WEB-INF/tiles-layouts/child/layout.jsp" />
    <put name="title" value="page title" />
    <put name="metaKeywords"    value="" />
    <put name="metaDescription" value="" />
    <put name="body"            value="/child/pagebody.jsp"/>
    <putList name="list">
        <add value="title" />
        <add value="metaKeywords" />
        <add value="metaDescription" />
        <add value="body" />
    </putList>
</definition>

<tiles:insert attribute="pageTemplate">
<tiles:put name="title"><tiles:getAsString name="title" /></tiles:put>
<tiles:put name="metaKeywords"><tiles:getAsString name="metaKeywords" /></tiles:put>
<tiles:put name="metaDescription"><tiles:getAsString name="metaDescription" /></tiles:put>
<tiles:put name="body"><tiles:getAsString name="body" /></tiles:put>

因为子定义并不总是包含相同的属性。有没有一种方法可以使用子定义中的putList将属性放入globalLayout.jsp?我试过以下方法,但失败了

<%@ page import="java.util.Iterator" %>
<tiles:importAttribute />
<bean:define id="list" name="list" type="java.util.List" scope="page" />
<tiles:insert attribute="pageTemplate" ignore="true" flush="true">
    <%
    for ( Iterator it = list.iterator(); it.hasNext(); ) {
        String item = (String) it.next();
    %>
        <tiles:put name="<%=item%>"><tiles:getAsString name="<%=item%>" ignore="true" /></tiles:put>
    <% } %>
</tiles:insert>