Well, then all these setOnXXX() should mention it as well, wouldn't you say?
Perhaps a better solution might be a general purpose tutorial which addresses the common pitfalls like memory leaks, and new features like Subscription. We do have these tutorials for java8 - https://docs.oracle.com/javase/8/javafx/events-tutorial/events.htm But since JavaFX has been decoupled from the JDK we don't seem to have anything more recent. I don't know whether this situation is going to change any time soon. -andy From: Thiago Milczarek Sayão <thiago.sa...@gmail.com> Date: Thursday, April 18, 2024 at 08:51 To: Andy Goryachev <andy.goryac...@oracle.com> Cc: openjfx-dev <openjfx-dev@openjdk.org> Subject: [External] : Re: Possible leak on setOnAction I was investigating, It probably should be menuItem.setOnAction(new WeakEventHandler<>(e -> stage.toFront())); But I bet it's a common mistake. Maybe the setOnAction should mention it? Em qui., 18 de abr. de 2024 às 11:54, Andy Goryachev <andy.goryac...@oracle.com<mailto:andy.goryac...@oracle.com>> escreveu: You are correct - the lambda strongly references `stage` and since it is in turn is strongly referenced from the menu item it creates a leak. The lambda is essentially this: menuItem.setOnAction(new H(stage)); class $1 implements EventHandler<ActionEvent> { private final Stage stage; public $1(Stage s) { this.stage = s; // holds the reference and causes the leak } public void handle(ActionEvent ev) { stage.toFront(); } } -andy From: openjfx-dev <openjfx-dev-r...@openjdk.org<mailto:openjfx-dev-r...@openjdk.org>> on behalf of Thiago Milczarek Sayão <thiago.sa...@gmail.com<mailto:thiago.sa...@gmail.com>> Date: Thursday, April 18, 2024 at 03:42 To: openjfx-dev <openjfx-dev@openjdk.org<mailto:openjfx-dev@openjdk.org>> Subject: Possible leak on setOnAction Hi, I'm pretty sure setOnAction is holding references. I have a "Open Windows" menu on my application where it lists the Stages opened and if you click, it calls stage.toFront(): menuItem.seOnAction(e -> stage.toFront()) I had many crash reports, all OOM. I got the hprof files and analyzed them - turns out this was holding references to all closed stages. To fix it, I call setOnAction(null) when the stage is closed. I will investigate further and provide an example. -- Thiago.
