@Override
 public void clearCachedAuthorizationInfo(PrincipalCollection principals) {
   super.clearCachedAuthorizationInfo(principals);
 }
 public void removeUserAuthorizationInfoCache(String username) {
   SimplePrincipalCollection pc = new SimplePrincipalCollection();
   pc.add(username, super.getName());
   super.clearCachedAuthorizationInfo(pc);
 }