如果仅满足条件，如何显示某些表单字段？

Question

我是jenkins插件创建的新手。我只想在表单验证成功时显示一组字段。例如 config.jelly包含

<f:entry title="App user">
   <f:textbox field="user" />
</f:entry>
<f:validateButton title="${%Test User}" progress="${%Testing...}" method="testUser" with="user" />

我正在按照以下节点api调用验证此用户

public FormValidation doTestUser(@QueryParameter("user") final String user) {
    int statusCode = validate(user);
    if(statusCode==200) {
         // how do I call another jelly file such as config2.jelly here to show further form fields? if its not 200 I dont want to show the config2.jelly
    }
}