assertEquals("1.2.840.48018.1.2.2", SpnegoConstants.LEGACY_KERBEROS_MECHANISM, "LEGACY_KERBEROS_MECHANISM mismatch");
        assertEquals("1.3.6.1.4.1.311.2.2.10", SpnegoConstants.NTLMSSP_MECHANISM, "NTLMSSP_MECHANISM mismatch");
    }

    @Test
    @DisplayName("Interface structure is as expected")
    void interfaceStructure() {
        Class<?> c = SpnegoConstants.class;

    /**
     * OID for the legacy Kerberos v5 mechanism
     */
    String LEGACY_KERBEROS_MECHANISM = "1.2.840.48018.1.2.2";

    /**
     * OID for the NTLMSSP mechanism
     */
    String NTLMSSP_MECHANISM = "1.3.6.1.4.1.311.2.2.10";

    private static final ASN1ObjectIdentifier OID_KRB_LEGACY = new ASN1ObjectIdentifier(SpnegoConstants.LEGACY_KERBEROS_MECHANISM);
    private static final ASN1ObjectIdentifier OID_NTLM = new ASN1ObjectIdentifier(SpnegoConstants.NTLMSSP_MECHANISM);
    private static final String SPNEGO_OID_STR = SpnegoConstants.SPNEGO_MECHANISM;

    // Helper to build a SPNEGO NegTokenInit as per NegTokenInit#toByteArray but parameterized for tests