} finally {
            der.close();
        }
        return collector.toByteArray();
    }

    @Test
    @DisplayName("Round-trip: all fields set encodes and parses back correctly")
    void testRoundTripAllFields() throws Exception {
        ASN1ObjectIdentifier[] mechs = new ASN1ObjectIdentifier[] { OID_KRB, OID_NTLM };
        int flags = NegTokenInit.DELEGATION | NegTokenInit.MUTUAL_AUTHENTICATION | NegTokenInit.INTEGRITY;