return null;
    }

    protected abstract SmbResource adapt(FileEntry e) throws MalformedURLException;

    /**
     * {@inheritDoc}
     *
     * @see java.util.Iterator#hasNext()
     */
    @Override
    public boolean hasNext() {
        return this.next != null;
    }

    /**
     * {@inheritDoc}
     *
     * @see java.util.Iterator#next()
     */
    @Override

        boolean guest = flags[1];

        // Arrange
        Subject subject = new Subject();
        TestCredentials creds = new TestCredentials("DOMAIN", anonymous, guest, subject, false);

        // Act & Assert
        // unwrap to interface itself should return same instance
        CredentialsInternal unwrapped = creds.unwrap(CredentialsInternal.class);
        assertNotNull(unwrapped, "unwrap to CredentialsInternal returns instance");

    @DisplayName("byte[] ctor: empty token throws PACDecodingException with clear message")
    void byteArrayConstructor_emptyToken_throws() {
        // Arrange
        byte[] empty = new byte[0];

        // Act + Assert
        PACDecodingException ex = assertThrows(PACDecodingException.class, () -> new KerberosApRequest(empty, new KerberosKey[0]));
        assertTrue(ex.getMessage().contains("Empty kerberos ApReq"));
    }

    @Test

    void defaultConstructor_hasNullMessageAndCause_andDefaultStatus() {
        // Arrange & Act
        SMBSignatureValidationException ex = new SMBSignatureValidationException();

        // Assert
        assertNull(ex.getMessage(), "Default ctor should not set a message");
        assertNull(ex.getCause(), "Default ctor should not set a cause");

        this.iterators = iterators;
    }

    @Override
    public boolean hasNext() {
        for (; index < iterators.length; ++index) {
            if (iterators[index].hasNext()) {
                return true;
            }
        }
        return false;
    }

    @Override
    public E next() {
        if (!hasNext()) {
            throw new NoSuchElementException();
        }

        // ## Arrange ##
        final ResultData resultData = new ResultData();
        final Object rawData = new Object();

        // ## Act ##
        resultData.setRawData(rawData);

        // ## Assert ##
        assertEquals(rawData, resultData.getRawData());

        assertNull(resultData.serializer);
        try {
            resultData.getData();
            fail();
        } catch (CrawlerSystemException e) {

        // Act
        out.close();

        // Assert
        verifyNoInteractions(handle);
    }

    @Nested
    @DisplayName("Constructor invalid inputs")
    class ConstructorInvalidInputs {
        @Test
        @DisplayName("Null handle triggers NullPointerException")
        void ctor_nullHandle_throwsNPE() {
            // Act + Assert

            // Act & Assert
            assertDoesNotThrow(() -> new MsrpcSamrConnect2(null, 0, ph));
        }

        @Test
        @DisplayName("should accept negative access mask values")
        void testNegativeAccessMaskAccepted() {
            // Arrange
            SamrPolicyHandle ph = createMockPolicyHandle();

            // Act & Assert

        // Assert - verify interaction with dependency
        verify(tree, times(1)).connectLogon(context);
        verify(tree, never()).close();
    }

    @Test
    @DisplayName("connectLogon accepts null context but still invokes")
    void connectLogon_withNull_isInvoked() throws Exception {
        // Act
        tree.connectLogon(null);

        // Arrange
        StaticJAASConfiguration cfg = new StaticJAASConfiguration();

        // Act
        AppConfigurationEntry[] entries = cfg.getAppConfigurationEntry("ignored");

        // Assert
        assertNotNull(entries, "Entries array should not be null");
        assertEquals(1, entries.length, "Exactly one entry is expected");
        AppConfigurationEntry e = entries[0];