如何使用xslt xquery序列化命名空间导出到JSON

我试图在这里使用WikiBooks中的“将XML转换为JSON”示例 https://en.wikibooks.org/wiki/XQuery/Convert_XML_to_JSON

xquery version "3.0";

declare namespace output="http://www.w3.org/2010/xslt-xquery-serialization";

declare option output:method "json";
declare option output:media-type "application/json";

let $test := <root>
  <!-- simple elements -->
  <aaa>AAA</aaa>
  <bbb>BBB</bbb>
  <ccc>CCC</ccc>
  <!-- complex (nested) element -->
  <ddd>
     <eee>
        <fff>
           <ggg>GGG</ggg>
        </fff>
     </eee>
  </ddd>
  <!-- duplicate elements -->
  <hhh>HHH1</hhh>
  <hhh>HHH2</hhh>
  <hhh>HHH3</hhh>
  <hhh>HHH4</hhh>
  <!-- attributes -->
  <iii a1="123" a2="456" a3="789"/>
  <!-- attributes with text content-->
  <jjj a1="123" a2="456" a3="789">JJJ</jjj>
</root>

return $test

我使用的是Saxon解析器,命令行

java -cp Saxon-HE-9.8.0-8.jar net.sf.saxon.Query xml2json.xqy

但它仍然以xml形式返回$test变量,我缺少了什么?