title: Design patterns for enabling user interface elements based on user permissions?
body: <p>We have a web application and its front end is implemented with GWT/GXT. Users can belong to various groups and these groups can then have various permissions. The permissions are quite fine grained, for example comment_create, comment_edit, comment_delete and comment_read.</p>
  
  <p>What would be the best way to enable and disable user interface controls based on user permissions? We have an utility method that returns boolean value with given user and permission name. But at the moment each control is wrapped inside if clause and that makes the code bit messy.</p>