// Constructor accepts null principal without throwing exception
        NtlmHttpServletRequest request = new NtlmHttpServletRequest(mockRequest, null);

        // getRemoteUser() will throw NPE when trying to call getName() on null principal
        assertThrows(NullPointerException.class, () -> request.getRemoteUser());
        assertNull(request.getUserPrincipal());
        assertEquals("NTLM", request.getAuthType());

    @Mock
    private Configuration mockConfig;

    private SmbComSetInformationResponse response;

    @BeforeEach
    void setUp() {
        // Setup mock configuration to avoid NPE
        when(mockConfig.getPid()).thenReturn(12345);

        response = new SmbComSetInformationResponse(mockConfig);
    }

    @Test
    @DisplayName("Constructor accepts valid config")

        assertFalse(handle.isSMB2());
    }

    @Test
    @DisplayName("Null treeConnection throws NPE")
    void constructorNullTreeConnection() {
        // Null treeConnection throws NPE when acquire() is called
        assertThrows(NullPointerException.class, () -> new SmbTreeHandleImpl(resourceLoc, null));
    }

    @Test

            assertEquals("Named pipes are only valid on IPC$", ex.getMessage());
        }

        @Test
        @DisplayName("Null context throws NPE (invalid input)")
        void nullContextThrows() {
            assertThrows(NullPointerException.class, () -> new SmbNamedPipe("smb://server/IPC$/foo", 0, null));
        }

        @Test

        assertThrows(NoSuchMethodException.class, () -> SessionSetupHandler.class.getDeclaredConstructor());
    }

    @Test
    @DisplayName("Invalid: resolving class by null name throws NPE")
    void testClassForNameWithNull() {
        // Intent: demonstrate defensive behavior with null when resolving this type by name
        assertThrows(NullPointerException.class, () -> Class.forName(null));
    }

    }

    // --- Invalid/null usage: calling a method on null should throw NPE ---
    @Test
    void nullReference_throwsNullPointerException() {
        // Arrange
        SmbBasicFileInfo info = null;

        // Act & Assert: attempting to call any method on null should throw NPE
        Assertions.assertThrows(NullPointerException.class, () -> {

            }
            return true; // not reached in this test
        };

        // Act + Assert
        NullPointerException npe = assertThrows(NullPointerException.class, () -> filter.accept(null));
        assertEquals("file must not be null", npe.getMessage());
    }

     * {@link NullPointerException}. This test is defensive; in real code it
     * would likely be handled elsewhere.
     */
    @Test
    @DisplayName("calling getters on null reference throws NPE")
    void testNullReference() {
        AllocInfo nullRef = null;
        assertThrows(NullPointerException.class, () -> nullRef.getCapacity());
        assertThrows(NullPointerException.class, () -> nullRef.getFree());
    }

        // Arrange
        Handler handler = newHandlerWith(mockCtx);

        // Act & Assert
        assertThrows(NullPointerException.class, () -> handler.openConnection(null), "Null URL should throw NPE");
        verify(mockCtx, never()).getConfig(); // no interaction expected on failure before construction
    }

    @Test
    @DisplayName("openConnection uses SingletonContext when no context provided")

    @DisplayName("Edge: calling renew() on a null reference throws NPE")
    void renewOnNullReferenceThrowsNPE() {
        // Arrange: null reference to the interface
        SmbRenewableCredentials creds = null;

        // Act + Assert: invoking renew() on null triggers NullPointerException
        assertThrows(NullPointerException.class, () -> {
            // Intentional NPE through dereference of a null interface reference