return (n & 1) == 0; // isEven()
              }
            }));
    assertEquals(newArrayList("1", "3", "5"), list);
    assertFalse(
        removeIf(
            transformed,
            new Predicate<Integer>() {
              @Override
              public boolean apply(Integer n) {
                return (n & 1) == 0; // isEven()
              }
            }));

    assertEquals(expected, actual);
  }

  @GwtIncompatible // unreasonably slow
  public void testFilterUsingIteratorTester() {
    List<Integer> list = asList(1, 2, 3, 4, 5);
    Predicate<Integer> isEven =
        new Predicate<Integer>() {
          @Override
          public boolean apply(Integer integer) {
            return integer % 2 == 0;
          }
        };
    new IteratorTester<Integer>(

    @DisplayName("isOpen delegates to handle.isOpen")
    void isOpen_delegates(boolean state) throws Exception {
        // Arrange
        SmbPipeOutputStream out = newStream();
        when(handle.isOpen()).thenReturn(state);

        // Act
        boolean result = out.isOpen();

        // Assert
        assertEquals(state, result, "isOpen should reflect handle state");

        /**
         * Verifies that the isOpen method returns true for an open handle.
         */
        @Test
        public void testIsOpen_ReturnsTrueWhenOpen() {
            when(smbPipeHandle.isOpen()).thenReturn(true);
            assertTrue(smbPipeHandle.isOpen(), "isOpen() should return true when the handle is open.");
        }

        /**
         * Verifies that the isOpen method returns false for a closed handle.

        super(handle.getPipe(), th, null, 0, 0, 0);
        this.handle = handle;
    }

    /**
     * {@inheritDoc}
     *
     * @see jcifs.smb.SmbFileOutputStream#isOpen()
     */
    @Override
    public boolean isOpen() {
        return this.handle.isOpen();
    }

    @Override
    protected synchronized SmbTreeHandleImpl ensureTreeConnected() throws CIFSException {
        return this.handle.ensureTreeConnected();
    }

        assertSame(pipe, handle.getPipe());
    }

    @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");

    }

    @Test
    void testClose() throws SmbException {
        // Mock isOpen to return false after close
        doAnswer(new Answer<Void>() {
            @Override
            public Void answer(InvocationOnMock invocation) throws Throwable {
                when(smbFile.isOpen()).thenReturn(false);
                return null;
            }
        }).when(smbFile).close(anyLong());

        // 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());

        // If handle becomes invalid, reflect stale

    }

    public String getUncPath() {
        return this.uncPath;
    }

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

    /**
     *
     * {@inheritDoc}
     *

     *
     * @return true if the stream is open, false otherwise
     */
    public boolean isOpen() {
        return file.isOpen();
    }

    void ensureOpen() throws IOException {
        // ensure file is open
        if (!file.isOpen()) {
            file.open(openFlags, access | SmbConstants.FILE_WRITE_DATA, SmbFile.ATTR_NORMAL, 0);
            if (append) {