SmbTreeHandleInternal t2 = handle.ensureTreeConnected();

        // Assert
        assertSame(tree, t1, "First acquire returns provided tree");
        assertSame(tree, t2, "Subsequent acquire returns same tree instance");
        verify(pipe, times(1)).ensureTreeConnected();
        verify(tree, times(2)).acquire();
    }

    @Test
    @DisplayName("getInput/getOutput return cached streams when open; throw when closed")

        SmbTreeHandleImpl t2 = h.getTree();

        assertSame(tree, t1, "Expected same mocked tree");
        assertSame(tree, t2, "Expected same mocked tree");

        // acquire is called once in ctor + once per getTree() call
        verify(tree, times(3)).acquire();
    }

    @Test
    @DisplayName("isValid() true when open, same tree id, connected")
    void isValid_true_whenOpenSameTreeConnected() {

     * <p>To avoid races between threads doing release and acquire, we transition to the final state
     * in two steps. One thread will successfully CAS from RUNNING to COMPLETING, that thread will
     * then set the result of the computation, and only then transition to COMPLETED, CANCELLED, or
     * INTERRUPTED.
     *
     * <p>We don't use the integer argument passed between acquire methods so we pass around a -1
     * everywhere.
     */

    @Mock
    SmbResource parent;
    @Mock
    ResourceNameFilter nameFilter;

    private void stubAcquireReturnsSelf() {
        when(tree.acquire()).thenReturn(tree);
    }

    @Test
    @DisplayName("Getters return constructor values and acquire is called")
    void gettersAndAcquire() throws Exception {
        // Arrange
        stubAcquireReturnsSelf();
        String wildcard = "*.*";

the header line. This behavior can be disabled with `GODEBUG=tracebacklabels=0`
(added in [Go 1.26](/doc/godebug#go-126)). This opt-out is expected to be
kept indefinitely in case goroutine labels acquire sensitive information that

                            log.debug("Acquire tree on first usage " + t);
                        }
                        t.acquire();
                        this.treeAcquired = true;
                    }
                }
                if (this.delegate != null && !this.delegateAcquired) {
                    log.debug("Acquire delegate on first usage");
                    this.delegate.acquire();

        }
    }

    /**
     * @return a file handle with increased usage count
     */
    public SmbFileHandleImpl acquire() {
        final long usage = this.usageCount.incrementAndGet();
        if (log.isTraceEnabled()) {
            log.trace(String.format("Acquire %s (%d)", this, usage));
        }
        return this;
    }

    /**
     *
     */
    public void markClosed() {

	// ErrIsNotEmpty is returned when the buffer is not empty and not blocking.
	ErrIsNotEmpty = errors.New("ringbuffer is not empty")

	// ErrAcquireLock is returned when the lock is not acquired on Try operations.
	ErrAcquireLock = errors.New("unable to acquire lock")

	// ErrWriteOnClosed is returned when write on a closed ringbuffer.
	ErrWriteOnClosed = errors.New("write on closed ringbuffer")
)

     */
    protected synchronized SmbFileHandleImpl ensureOpen() throws CIFSException {
        if (!isOpen()) {
            // one extra acquire to keep this open till the stream is released
            this.handle = this.file.openUnshared(this.openFlags, this.access, this.sharing, SmbConstants.ATTR_NORMAL, 0).acquire();
            if (this.append) {
                this.fp = this.handle.getInitialSize();
                if (log.isDebugEnabled()) {

		// 3) lk3 or lk4 (whichever didn't execute in step 1) then executes and creates
		//    a new entry in lockMap and acquires a lock for the same resource.

		<-lk2ch
		lk3ok := <-lk3ch
		lk4ok := <-lk4ch

		if lk3ok && lk4ok {
			t.Fatalf("multiple locks acquired; iteration=%d, lk3=%t, lk4=%t", i, lk3ok, lk4ok)
		}
	}