title: Struts2 disable <s:textfield> using some expression
body: <p>I have two roles in my app, ROLE_ADMIN &amp; ROLE_USER
  Also I have a form with some fields. I would like to have the following:
  When user has ADMIN role he is able to edit specific group of fields, when user has USER role he is not able to edit these fields. I don't want to have two different forms, or two copies of fields for every role.</p>
  
  <p>I tried to do something like that:</p>
  
  <p>&lt;s:textfield key="..." <strong>disabled="${myFlag}"</strong> &gt;, where myFlag evaluated from roles.</p>
  
  <p>But I have warning "disabled" does not support runtime expressions.</p>
  
  <p>Is there any way to do this? Or maybe there's better way, for example, by replacing generated input to label ?</p>
  
  <p>Thanks in advance.</p>