RFR: 8364088: ToolBarSkin: NPE in select()

[Andy Goryachev]

On Fri, 25 Jul 2025 22:32:36 GMT, Andy Goryachev <angorya at openjdk.org> wrote:

> Fixed an NPE in the ToolBar, looks like a corner case.

> Is this unit-testable?
> Any minimal test case?

Github ate my previous response!  Restoring from memory.

The bug came out of testing JDK-8364049.  I could not create a headless unit test: it looks like the focus subsystem is involved which is not easily reproducible with a headless test.  I don't want to create a headful test for this particular scenario.

For the record, the test I tried to write:


    @Test
    public void testNPE_8364088() {
        BorderPane bp = new BorderPane();
        Button b = new Button("Create Schema Overflow");
        bp.setTop(new HBox(new ToolBar(b)));
        Stage stage = new Stage();
        stage.setScene(new Scene(bp, 600, 400));
        stage.setTitle(getClass().getSimpleName());
        stage.show();

        runLater(() -> {
            b.requestFocus();
            runLater(() -> {
                stage.setWidth(50);
                runLater(() -> {
                    stage.setWidth(40);
                    System.out.println(stage.getWidth());
                    stage.hide();
                });
            });
        });
    }
    
    private static void runLater(Runnable r) {
        AtomicInteger counter = new AtomicInteger(10);
        Platform.runLater(new Runnable() {
            @Override
            public void run() {
                if (counter.decrementAndGet() > 0) {
                    Platform.runLater(this);
                } else {
                    r.run();
                }
            }
        });
    }

-------------

PR Comment: https://git.openjdk.org/jfx/pull/1857#issuecomment-3132918888