Freemarker遍歷列表中的哈希映射鍵

Question

找到答案：$ {account [prop]}代替$ {account.get（prop）}有效

帳戶是具有以下類型的地圖列表

//[{"id":"1","location":"warehouse1"},{"id":"2","location":"warehouse2"}]
ArrayList<HashMap<String, String>> t = m.t();
root.put("accounts", t);
Writer out = null;
try {
    out = context.response.getWriter();
    T.getViewTpl(tplName).process(root, out);
} catch (IOException | TemplateException ex) {
    T.logger.error(T.class.getName(), ex);
} finally {
    try {
        out.close();
    } catch (IOException ex) {
        T.logger.error(T.class.getName(), ex);
    }
}

它將被呈現為表格。 一個帳戶一行，一個帳戶一列的屬性。 下面的代碼不起作用。 怎么做？ 提前致謝！

<table>
    <#list accounts as account>
    <tr>
        <#list account?keys as prop>
        <td>${account.get(prop)}</td>
        </#list>
    </tr>
    </#list>  
</table>

Freemarker錯誤為：

FreeMarker template error

The following has evaluated to null or missing:
==> account.get  [in template "account.tpl" at line 14, column 23]

Answer 1

這應該更好，您可能在從此處復制時忘記了將用戶更改為帳戶；）

<table>
<#list accounts as account>
    <tr>
    <#list account?keys as prop>
        <td>${account[prop]}</td>
    </#list>
    </tr>
</#list>  
</table>

Answer 2

Check null condition before iterating a list or map

<table>
<#if accounts??>
<#list accounts as account>
    <tr>
    <#list account?keys as prop>
        <td>${account[prop]}</td>
    </#list>
    </tr>
</#list>  
</#if>
</table>