@DisplayName("Should throw exception for null encryption key")
    void testNullEncryptionKey() {
        // When/Then
        assertThrows(NullPointerException.class, () -> {
            new Smb2EncryptionContext(1, DialectVersion.SMB311, null, testDecryptionKey);
        }, "Should throw NullPointerException for null encryption key");
    }

    @Test
    @DisplayName("Should throw exception for null decryption key")

        SmbRandomAccessFile raf = newInstance("rw", false, true, false);
        assertThrows(NullPointerException.class, () -> raf.read((byte[]) null));
        assertThrows(NullPointerException.class, () -> raf.writeBytes(null));
        assertThrows(NullPointerException.class, () -> raf.writeChars(null));
        assertThrows(NullPointerException.class, () -> raf.writeUTF(null));
    }

    @DisplayName("Reading with null array throws NullPointerException")
    void readNullArrayThrowsException() {
        // Create stream with valid message header and data
        byte[] data = new byte[] { 1 };
        InputStream in = new ByteArrayInputStream(concat(messageHeader(1), data));
        SocketInputStream sis = new SocketInputStream(in);

        // Should throw NullPointerException when reading with null array

    void openCopyTargetFile_nullDest_throwsNPE() {
        // Arrange
        SmbFile dest = null;

        // Act + Assert
        assertThrows(NullPointerException.class, () -> SmbCopyUtil.openCopyTargetFile(dest, SmbConstants.ATTR_NORMAL, false));
    }

    // --- Tests for copyFile exception handling branch ---

    @Nested
    class CopyFileExceptions {

        }
    }

    /**
     * Test that try-with-resources handles null InputStream correctly.
     * Verifies that null InputStream doesn't cause NullPointerException during close.
     */
    @Test
    public void testTryWithResources_nullInputStreamSafety() {
        // This test demonstrates that try-with-resources handles null safely
        try (InputStream is = null) {

        // Create a real NtlmPasswordAuthentication instance
        auth = new NtlmPasswordAuthentication("TESTDOMAIN", "testuser", "testpass");

        // Initialize ServerData to avoid NullPointerException
        SmbTransport.ServerData serverData = transport.new ServerData();
        serverData.security = 0; // Set to 0 or appropriate value for SECURITY_SHARE

        @DisplayName("Should handle null file ID during write")
        void testWriteWithNullFileId() {
            request.setFileId(null);
            byte[] buffer = new byte[256];

            assertThrows(NullPointerException.class, () -> request.writeBytesWireFormat(buffer, 0));
        }

        @Test
        @DisplayName("Should handle file ID of different sizes")
        void testWriteWithDifferentFileIdSizes() {

        });
    }

    @Test
    void constructor_shouldThrowExceptionWithNullSids() {
        // Act & Assert - Null SID array causes NPE when accessing length
        assertThrows(NullPointerException.class, () -> {
            new MsrpcLookupSids(mockPolicyHandle, null);
        });
    }

    @Test
    void constructor_shouldSetCorrectSuperclassParameters() throws Exception {
        // Arrange

        Smb2FlushRequest requestWithNull = new Smb2FlushRequest(mockConfig, null);
        byte[] buffer = new byte[256];

        // Should throw NullPointerException when trying to copy null array
        assertThrows(NullPointerException.class, () -> {
            requestWithNull.writeBytesWireFormat(buffer, 0);
        });
    }

    @Test
    @DisplayName("readBytesWireFormat should return 0")

            unicodeString.check("");
        });

        // The implementation has a bug - it doesn't handle null properly
        // It throws NullPointerException instead of returning null
        // This is a known issue in the production code
        assertThrows(NullPointerException.class, () -> {
            unicodeString.check(null);
        });
    }

    @Test