struts2 iterator 嵌套循环，内iterator取外iterator的属性....
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<s:iterator value="groupsList" var="st">
<s:iterator value="userList">
<input type="checkbox" name="giveUsers" id="users" value="${st.id}-${id}"/>${loginName}
</s:iterator>
</s:iterator>
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${st.id}是当前外iterator的ID，${id}是内iterator的ID
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List<Double> incomeList = Lists.newArrayList();
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<s:iterator value="incomeList" id="offset">
<td>
<s:property value="#offset"/>
</td>
</s:iterator>
