}

        @Test
        @DisplayName("Should throw IOException when handle is stale")
        void testDoSendReceiveFragment_StaleHandle() throws Exception {
            DcerpcPipeHandle handle = createMockedDcerpcPipeHandle();
            when(mockSmbPipeHandleInternal.isStale()).thenReturn(true);

        /**
         * Verifies that isStale returns false for a fresh handle.
         */
        @Test
        public void testIsStale_ReturnsFalseWhenNotStale() {
            when(smbPipeHandle.isStale()).thenReturn(false);
            assertFalse(smbPipeHandle.isStale(), "isStale() should return false for a fresh handle.");
        }

        /**
         * Verifies that isStale returns true for a stale handle.
         */

        // Initially not open (isStale returns false when handle is null, not true)
        assertFalse(target.isOpen());
        assertFalse(target.isStale());

        // After ensureOpen, handle valid -> open
        SmbFileHandleImpl fh = target.ensureOpen();
        assertSame(fileHandle, fh);
        assertTrue(target.isOpen());
        assertFalse(target.isStale());

    }

    @Test
    @DisplayName("isOpen/isStale reflect handle validity and lifecycle")
    void isOpen_isStale_transitions() throws Exception {
        SmbPipeHandleImpl handle = newHandleWithBasicStubs(0, "\\\\pipe\\\\w");
        assertFalse(handle.isOpen(), "Initially not open");
        assertFalse(handle.isStale(), "Initially not stale");

        // After ensureOpen with valid fh

    boolean isOpen();

    /**
     * Tests whether this file descriptor was previously open but has become invalid.
     *
     * @return whether the FD was previously open but became invalid
     */
    boolean isStale();

    /**
     * Unwraps this handle to the specified type.
     *
     * @param <T> the type to unwrap to
     * @param type the class of the type to unwrap to
     * @return unwrapped instance
     */

     */
    @Override
    protected int doSendReceiveFragment(final byte[] buf, final int off, final int length, final byte[] inB) throws IOException {
        if (this.handle.isStale()) {
            throw new IOException("DCERPC pipe is no longer open");
        }

        int have = this.handle.sendrecv(buf, off, length, inB, getMaxRecv());

            return sess.getSessionKey();
        }
    }

    /**
     * {@inheritDoc}
     *
     * @see jcifs.SmbPipeHandle#isStale()
     */
    @Override
    public boolean isStale() {
        return !this.open || this.handle != null && !this.handle.isValid();
    }

    @Override
    public synchronized SmbFileHandleImpl ensureOpen() throws CIFSException {

                final long numOfDeleted = searchEngineClient.deleteByQuery(index, queryBuilder);
                logger.info("[{}] Deleted {} stale documents.", dataConfig.getName(), numOfDeleted);
            } catch (final Exception e) {
                logger.error("[{}] Failed to delete stale documents.", dataConfig.getName(), e);
            }
        }

        /**
         * Checks if the crawling thread has finished execution.

                final long deletedDocCount = deleteOldDocuments(searchEngineClient, docList);
                if (logger.isDebugEnabled()) {
                    logger.debug("Deleted {} stale documents", deletedDocCount);
                }
                final BulkResponse response =
                        searchEngineClient.addAll(fessConfig.getIndexDocumentUpdateIndex(), docList, (doc, builder) -> {

            try {
                return send0(loc, request, response, params);
            } catch (final SmbException smbe) {
                // Retrying only makes sense if the invalid parameter is an tree id. If we have a stale file descriptor
                // retrying make no sense, as it will never become available again.
                if (params.contains(RequestParam.NO_RETRY)