urlFilter.init(sessionId);

        try {
            urlFilter.processUrl(null);
            // Should handle null gracefully or throw appropriate exception
        } catch (NullPointerException e) {
            // Expected behavior for null input
            assertTrue(true);
        }
    }

    /**
     * Test processUrl with empty URL
     */

    }

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

    @Test
    @DisplayName("Null resourceLoc is accepted but may cause issues later")
    void constructorNullResourceLoc() {

            TestDcerpcHandle handleWithNullBinding = new TestDcerpcHandle(mockContext);

            // When/Then: Should throw NPE for null binding (expected behavior)
            assertThrows(NullPointerException.class, () -> handleWithNullBinding.toString());
        }

        @Test
        @DisplayName("Should handle session key retrieval")
        void testSessionKeyRetrieval() throws CIFSException {

        // keep retries small for faster and deterministic tests
        when(config.getMaxRequestRetries()).thenReturn(2);
        when(config.isTraceResourceUsage()).thenReturn(false);
        // Mock credentials to avoid NullPointerException
        when(ctx.getCredentials()).thenReturn(credentials);
        when(credentials.getUserDomain()).thenReturn("DOMAIN");
        // Mock DFS resolver
        when(ctx.getDfs()).thenReturn(dfsResolver);
    }

            // The implementation calls Hexdump.toHexString which throws NPE on null
            // This test verifies the actual behavior
            assertThrows(NullPointerException.class, () -> notification.toString());
        }

        @ParameterizedTest
        @DisplayName("Should format different oplock levels correctly")

        SIDCacheImpl cache = new SIDCacheImpl(mock(CIFSContext.class));
        CIFSContext ctx = mock(CIFSContext.class);

        // Null sids array -> NPE
        assertThrows(NullPointerException.class, () -> cache.resolveSids(ctx, "server", null, 0, 1));

        // Bad offset/length leads to ArrayIndexOutOfBoundsException
        jcifs.SID[] sids = new jcifs.SID[] { sid("S-1-1-0") };

        });
    }

    @Test
    @DisplayName("Should handle parsing null message bytes")
    void testNullMessageBytes() {
        // When/Then
        assertThrows(NullPointerException.class, () -> {
            new Type3Message((byte[]) null);
        });
    }

    /**
     * Helper method to create a mock Type 2 message for testing
     */

            buffer = new DfsReferralRequestBuffer(path, maxReferralLevel);
            assertNotNull(buffer);

            // Will throw NPE when trying to call size() or encode()
            assertThrows(NullPointerException.class, () -> {
                buffer.size();
            });
        }

        @ParameterizedTest
        @DisplayName("Should handle various referral levels")

     *
     * @param dest
     *            An <code>SmbResource</code> that represents the new pathname
     * @throws CIFSException if an error occurs renaming the resource
     * @throws NullPointerException
     *             If the <code>dest</code> argument is <code>null</code>
     */
    void renameTo(SmbResource dest) throws CIFSException;

    /**

        // Register should fail with null container
        try {
            ruleWithoutContainer.register(0);
            fail("Should throw exception with null container");
        } catch (NullPointerException e) {
            // Expected
        }
    }

    /**
     * Test concurrent property access
     */
    public void test_concurrentPropertyAccess() throws Exception {