SmbAuthException ex = new SmbAuthException(errCode);

        // Assert: type, message derived from code, status mapping, and no cause
        assertNotNull(ex);
        assertTrue(ex instanceof SmbException);
        assertEquals(SmbException.getMessageByCode(errCode), ex.getMessage(), "message should reflect error code mapping");
        assertEquals(expectedStatus, ex.getNtStatus(), "status should map based on code");

        // Act & Assert: both UnknownHostException and IOException should become CIFSException (SmbException)
        CIFSException ex = assertThrows(CIFSException.class, () -> trace.connectWrapException(loc));
        assertTrue(ex.getMessage() != null && ex.getMessage().contains("Failed to connect to server"));
        assertSame(thrown, ex.getCause());
    }

    @Test
    @DisplayName("connectWrapException: rethrows SmbException unchanged")

        try {
            digest = MessageDigest.getInstance("MD5");
        } catch (final NoSuchAlgorithmException ex) {
            if (LogStream.level > 0) {
                ex.printStackTrace(log);
            }
            throw new SmbException("MD5", ex);
        }

        this.macSigningKey = macSigningKey;
        this.bypass = bypass;
        this.updates = 0;
        this.signSequence = 0;

        // Arrange & Act
        SmbUnsupportedOperationException ex = new SmbUnsupportedOperationException();

        // Assert
        assertEquals("Operation is not supported with the negotiated capabilities", ex.getMessage(),
                "Default message should match the class contract");
        assertNull(ex.getCause(), "No cause expected from default constructor");
        assertTrue(ex instanceof SmbException, "Should be an SmbException");

                        try {
                            handlerClass = Class.forName(className);
                        } catch (final Exception ex) {
                            log.debug("Failed to load handler class " + className, ex);
                        }
                        if (handlerClass == null) {
                            handlerClass = ClassLoader.getSystemClassLoader().loadClass(className);

        return connection.getDate();
    }

    @Override
    public long getLastModified() {
        try {
            handshake();
        } catch (final IOException ex) {}
        return connection.getLastModified();
    }

    @Override
    public String getHeaderField(final String header) {
        try {
            handshake();
        } catch (final IOException ex) {}

    void getSessionKey_throws() throws CIFSException {
        doThrow(new CIFSException("session key failure")).when(session).getSessionKey();

        CIFSException ex = assertThrows(CIFSException.class, () -> session.getSessionKey());
        assertTrue(ex.getMessage().contains("failure"));
        verify(session).getSessionKey();
    }

    // Happy path: transport is returned and verified
    @Test

        // Act + Assert: exception is propagated with message
        CIFSException ex = assertThrows(CIFSException.class, () -> handle.ensureDFSResolved());
        assertEquals("DFS resolution failed", ex.getMessage());
        verify(handle, times(1)).ensureDFSResolved();
    }

    @ParameterizedTest

    private final RuntimeException ex;

    private ThrowingIterator(RuntimeException ex) {
      this.ex = ex;
    }

    @Override
    public boolean hasNext() {
      // IteratorTester doesn't expect exceptions for hasNext().
      return true;
    }

    @Override
    public E next() {
      ex.fillInStackTrace();
      throw ex;
    }

    @Override

    private final RuntimeException ex;

    private ThrowingIterator(RuntimeException ex) {
      this.ex = ex;
    }

    @Override
    public boolean hasNext() {
      // IteratorTester doesn't expect exceptions for hasNext().
      return true;
    }

    @Override
    public E next() {
      ex.fillInStackTrace();
      throw ex;
    }

    @Override