On Thu, 29 Sep 2022 23:00:17 GMT, Andy Goryachev <ango...@openjdk.org> wrote:
> Fixed memory leak by using weak listeners and making sure to undo everything
> that has been done to MenuBar/Skin in dispose().
modules/javafx.controls/src/main/java/javafx/scene/control/skin/MenuBarSkin.java
line 328:
> 326: mouseEventHandler = t -> {
> 327: if (getSkinnable() != null) {
> 328: Bounds containerScreenBounds =
> container.localToScreen(container.getLayoutBounds());
this null check is wrong: skinnable is guaranteed to never be null - except
after dispose, at which time it's illegal to access any of the skin's
methods/fields/state. So checking here is smearing over a precondition
violation of the caller (most probably a dangling handler/listener) which has
to be fixed.
Note we deliberately removed all null checks in all (cleaned) skins :) If we
see any exceptions, the procedure is to
- write a test exposing the exception (it's failing), this test belongs into
SkinCleanTest
- find and fix the violator
- see the test passing
There might be other exceptions as well (like IOOB or similar) which require a
similar procedure, see the available tests. Actually, I think it's a good idea
to actively look out for possible macroscopic misbehavior if handlers/listeners
are not removed properly. SkinCleanupTest has examples.
-------------
PR: https://git.openjdk.org/jfx/pull/906
