assertTrue(ex.getMessage().toLowerCase().contains("null"));
    }

    @Test
    @DisplayName("toByteArray returns empty when no mechanismToken")
    void toByteArrayWhenNull() {
        TestSpnegoToken t = new TestSpnegoToken();
        assertArrayEquals(new byte[0], t.toByteArray(), "empty array expected when mechanismToken is null");
    }

    @Test