@Override
    public Collection<Permission> getPermissions(Action action) {
        if (!(action instanceof DestinationAction)) {
            throw new IllegalArgumentException("Action argument must be a " + DestinationAction.class.getName() + " instance.");
        }
        DestinationAction da = (DestinationAction) action;
        return getPermissions(da);
    }
@Test(expected = IllegalArgumentException.class)
    public void testGetPermissionsWithNullArgument() {
        resolver.getPermissions((Action)null);
    }