assertFalse(empty.isSupported(new ASN1ObjectIdentifier("1.2.3")));
            assertFalse(empty.isPreferredMech(new ASN1ObjectIdentifier("1.2.3")));
            assertFalse(empty.isPreferredMech(null));
            assertFalse(empty.isSupported(null));
            assertEquals("", empty.getNetbiosName(), "supports empty NetBIOS name");
        }
    }

    }

    @Test
    @DisplayName("isPreferredMech delegates to underlying mechanism context")
    void testIsPreferredMechDelegates() {
        SpnegoContext ctx = newContext();
        ASN1ObjectIdentifier mech = new ASN1ObjectIdentifier("1.2.840.113554.1.2.2");
        when(this.mechContext.isPreferredMech(mech)).thenReturn(true);
        assertTrue(ctx.isPreferredMech(mech));

    }

    /**
     * {@inheritDoc}
     *
     * @see jcifs.smb.SSPContext#isPreferredMech(org.bouncycastle.asn1.ASN1ObjectIdentifier)
     */
    @Override
    public boolean isPreferredMech(final ASN1ObjectIdentifier mech) {
        return this.mechContext.isPreferredMech(mech);
    }

    @Override
    public byte[] calculateMIC(final byte[] data) throws CIFSException {

    }

    /**
     * {@inheritDoc}
     *
     * @see jcifs.smb.SSPContext#isPreferredMech(org.bouncycastle.asn1.ASN1ObjectIdentifier)
     */
    @Override
    public boolean isPreferredMech(final ASN1ObjectIdentifier mechanism) {
        return this.auth.isPreferredMech(mechanism);
    }

    @Override
    public boolean isEstablished() {
        return this.isEstablished;
    }

    void isPreferredMech_nonAnonymous(ASN1ObjectIdentifier oid, boolean expected) {
        Kerb5Authenticator auth = new Kerb5Authenticator(new Subject());
        assertEquals(expected, auth.isPreferredMech(oid));
    }

    static Object[][] preferredMechData_anonymous() {
        return new Object[][] { { NtlmContext.NTLMSSP_OID, true }, { Kerb5Context.SUPPORTED_MECHS[0], false } };
    }

    }

    /**
     * {@inheritDoc}
     *
     * @see jcifs.smb.NtlmPasswordAuthenticator#isPreferredMech(org.bouncycastle.asn1.ASN1ObjectIdentifier)
     */
    @Override
    public boolean isPreferredMech(ASN1ObjectIdentifier mechanism) {
        if (isAnonymous()) {
            return super.isPreferredMech(mechanism);
        }
        return PREFERRED_MECHS.contains(mechanism);
    }

    /**

    /**
     * Checks whether the specified mechanism is the preferred mechanism.
     * @param selectedMech the selected mechanism OID
     * @return whether the specified mechanism is preferred
     */
    boolean isPreferredMech(ASN1ObjectIdentifier selectedMech);

    /**
     * Gets the negotiated context flags.
     * @return context flags
     */
    int getFlags();

    /**

    }

    /**
     * {@inheritDoc}
     *
     * @see jcifs.smb.SSPContext#isPreferredMech(org.bouncycastle.asn1.ASN1ObjectIdentifier)
     */
    @Override
    public boolean isPreferredMech(ASN1ObjectIdentifier mechanism) {
        return isSupported(mechanism);
    }

    /**
     * {@inheritDoc}
     *

        assertTrue(ctx.isSupported(oid));
        assertTrue(ctx.isPreferredMech(oid));
    }

    @Test
    @DisplayName("isSupported returns false for null/unknown OIDs")
    void isSupported_unknownOrNull() {
        assertFalse(ctx.isSupported(null));
        assertFalse(ctx.isPreferredMech(null));
        assertFalse(ctx.isSupported(new ASN1ObjectIdentifier("1.3.6.1.4.1.99999")));
    }

     *
     * @param mechanism the mechanism to check
     * @return whether the given mechanism is the preferred one for this credential
     */
    public boolean isPreferredMech(ASN1ObjectIdentifier mechanism) {
        return NtlmContext.NTLMSSP_OID.equals(mechanism);
    }

    /**
     * Computes the 24 byte ANSI password hash given the 8 byte server challenge.
     *