title: How to check if authority exists in a collection of GrantedAuthority?
body: <pre><code>Authentication auth = SecurityContextHolder.getContext().getAuthentication();
  Collection&lt;? extends GrantedAuthority&gt; roles = auth.getAuthorities();
  </code></pre>
  
  <p>How can I check if <code>roles</code> contains a specific authority like <code>"ROLE_ADMIN"</code>?</p>