title: JAXB-WS - Making a field mandatory using @WebMethod
body: <p>I have a @WebMethod call</p>
  
  <pre><code>@WebMethod
  public int cancelCampaign(String campaignId, String reason);
  </code></pre>
  
  <p>I'd like to make the campaignId field marked as mandatory. Not sure how to do that.</p>
  
  <p>I'm using a JBOSS 7.1 server.</p>