Field commandField = ServerMessageBlock2.class.getDeclaredField("command");
        commandField.setAccessible(true);
        int command = (int) commandField.get(request);
        assertEquals(0x0007, command); // SMB2_FLUSH value

        // Verify file ID is set
        Field fileIdField = Smb2FlushRequest.class.getDeclaredField("fileId");
        fileIdField.setAccessible(true);

        pos += 2;
        // 2 reserved bytes
        pos += 2;
        // ctlCode
        SMBUtil.writeInt4(ctlCode, buf, pos);
        pos += 4;
        // fileId (16 bytes)
        byte[] fid = fileId != null ? fileId : new byte[16];
        System.arraycopy(fid, 0, buf, pos, 16);
        pos += 16;

        // Calculate offsets relative to start of SMB2 header

    class SpecialValueConstants {

        @Test
        @DisplayName("Unspecified FileId should be 16 bytes of 0xFF")
        void testUnspecifiedFileId() {
            assertNotNull(Smb2Constants.UNSPECIFIED_FILEID, "Unspecified FileId should not be null");
            assertEquals(16, Smb2Constants.UNSPECIFIED_FILEID.length, "Unspecified FileId must be exactly 16 bytes");

            // Verify all bytes are 0xFF

        assertEquals((short) 0x0011, request.getCommand());

        // Verify that default file ID is set
        byte[] expectedFileId = Smb2Constants.UNSPECIFIED_FILEID;
        Field fileIdField;
        try {
            fileIdField = Smb2SetInfoRequest.class.getDeclaredField("fileId");
            fileIdField.setAccessible(true);
            byte[] actualFileId = (byte[]) fileIdField.get(request);

        assertEquals((short) 0x0010, request.getCommand());

        // Verify that default file ID is set
        byte[] expectedFileId = Smb2Constants.UNSPECIFIED_FILEID;
        Field fileIdField;
        try {
            fileIdField = Smb2QueryInfoRequest.class.getDeclaredField("fileId");
            fileIdField.setAccessible(true);
            byte[] actualFileId = (byte[]) fileIdField.get(request);

        when(cfg.isTraceResourceUsage()).thenReturn(false);
        stubValidTree(5L, true, true);

        byte[] fileId = new byte[] { 0x0A, 0x0B };
        SmbFileHandleImpl h = new SmbFileHandleImpl(cfg, fileId, tree, "//server/share/path", 0x1, 0x2, 0x3, 0x4, 123L);

        h.close(777L);

        // Verify SMB2 close path

            // Test with special characters in fileName
            String specialFileName = "file!@#$%^&*()_+-=[]{}|;':\",./<>?.txt";
            Smb2CloseResponse specialNameResponse = new Smb2CloseResponse(mockConfig, testFileId, specialFileName);
            assertEquals(specialFileName, specialNameResponse.getFileName());

            // Test with different fileId patterns
            byte[] zeroFileId = new byte[16];

    private void setupSmb2(NotifyResponse resp, byte[] fileId) throws Exception {
        when(handle.isValid()).thenReturn(true);
        when(handle.getTree()).thenReturn(tree);
        when(tree.isSMB2()).thenReturn(true);
        when(tree.getConfig()).thenReturn(mock(Configuration.class));
        when(handle.getFileId()).thenReturn(fileId);

     */
    public static final int FILE_OPEN_IF = 0x3;
    /**
     * If file exists, overwrite it. Otherwise fail
     */
    public static final int FILE_OVERWRITE = 0x4;
    /**
     * If file exists, overwrite it. Otherwise create the file
     */
    public static final int FILE_OVERWRITE_IF = 0x5;

    /**
     * File being created or opened must be a directory

        Smb2IoctlRequest request = new Smb2IoctlRequest(mockConfig, TEST_CONTROL_CODE);
        byte[] newFileId = new byte[16];
        Arrays.fill(newFileId, (byte) 0x55);

        request.setFileId(newFileId);
        // FileId is set internally
        assertNotNull(request);
    }

    @Test
    @DisplayName("Test createResponse method")
    void testCreateResponse() {