BufferCacheImpl impl = new BufferCacheImpl(cacheSize, 6);
        byte[] toRelease = new byte[5];
        toRelease[0] = 42;
        impl.releaseBuffer(toRelease);

        byte[] fromCache = impl.getBuffer();
        assertSame(toRelease, fromCache, "Released buffer should be returned from cache regardless of cache size");
        // Zeroed upon release
        for (byte value : fromCache) {
            assertEquals(0, value);

        // Test release (still in use because of initial transport acquire)
        session.release();
        assertTrue(session.isInUse(), "Session should still be in use after one release");

        // Test final release
        session.release();
        assertFalse(session.isInUse(), "Session should not be in use after all releases");

        // Test multiple releases (should not throw)

        // if some regions were pooled rather than immediately released)
        assertTrue(bufferManager.getTotalReleased() > 0, "Some regions should be released during cleanup");
        assertEquals(allocatedBeforeCleanup, bufferManager.getTotalReleased(),
                "All allocated regions should eventually be released after cleanup");
    }

    @Test
    public void testPooling() throws Exception {

        h.acquire();

        // First release: should not close yet
        h.release();
        verify(tree, never()).send(isA(Smb2CloseRequest.class), any());
        verify(tree, never()).send(any(CommonServerMessageBlockRequest.class), any(SmbComBlankResponse.class), any(RequestParam[].class));

        // Second release: should close now via SMB2 path
        h.release();

    }

    /**
     * Get total number of regions released
     *
     * @return total released regions
     */
    public long getTotalReleased() {
        return totalReleased.get();
    }

    /**
     * Get number of currently active regions
     *
     * @return active regions (allocated - released)
     */
    public long getActiveRegions() {

    }

    @Test
    @DisplayName("close/release manage usage and transport lifecycle")
    void testReleaseLifecycle() {
        SmbSessionImpl session = newSession();

        // First release drops usage to zero and releases transport
        session.release();
        verify(transport, times(1)).release();
        assertFalse(session.isInUse());

        // Next release goes below zero and throws

    @Test
    @DisplayName("close calls release and decrements usage; double release throws")
    void closeAndReleaseBehavior() {
        // Validates usage counting and that an extra release() throws RuntimeCIFSException
        // First close -> usage 1 -> 0, triggers treeConnection.release()
        handle.close();
        verify(treeConnection, times(1)).release();

        // Second release -> usage 0 -> -1 triggers RuntimeCIFSException

        verify(tree, times(1)).acquire();

        // Act: first release does not release yet (usage -> 1)
        c.release();
        verify(tree, never()).release();

        // Act: second release (usage -> 0) releases the tree
        c.release();
        verify(tree, times(1)).release();
    }

    @Test
    @DisplayName("release below zero throws RuntimeCIFSException")
    void release_belowZero_throws() {

    @Test
    void testRelease_throwsCIFSException() throws CIFSException {
        doThrow(new CIFSException("Failed to release")).when(smbFileHandle).release();
        assertThrows(CIFSException.class, () -> smbFileHandle.release(), "release() should throw CIFSException when releasing fails.");
        verify(smbFileHandle, times(1)).release();
    }

    /**
     * Test getInitialSize() returns the correct size.
     */
    @Test

            buffers.add(buffer);
        }

        // When - Release all buffers back
        for (byte[] buffer : buffers) {
            BufferCache.releaseBuffer(buffer);
        }

        // Then - Should be able to get buffers again
        byte[] newBuffer = BufferCache.getBuffer();
        assertNotNull(newBuffer, "Should be able to get buffer after release");