On Tue, 4 Nov 2025 09:06:41 GMT, Prasanta Sadhukhan <[email protected]> wrote:
> It is seen that when we close the SwingNode window while we have registered a > WINDOW_HIDDEN listener, it will cause a NPE > This is because WINDOW_HIDDEN listener called > `SwingNode.overrideNativeWindowHandle` to provide a native FX window handle > to AWT/Swing via JNI code, which gives provision to AWT/Swing code in > sun/swing/JLightweightFrame.java#overrideNativeWindowHandle to handle the > window closing > > https://github.com/openjdk/jdk/blob/e4aed95cac343f1339b9bc87721561bdc4c2f5ad/src/java.desktop/share/classes/sun/swing/JLightweightFrame.java#L527-L534 > > But if window is closed, then the node is removed from scene and > `SwingNode.disposeLwFrame` is called which nulls "lwFrame" which is the > handle for JLightweightFrame AWT frame, so when JNI code > https://github.com/openjdk/jfx/blob/c77c2335856a967907aaacc9546f44943c069add/modules/javafx.graphics/src/main/native-prism/SwingInterop.c#L47 > > tries to call JLightweightFrame, it crashes. > Fix is made to check for `lwFrame `before `overrideNativeWindowHandle ` is > called inside `SwingNodeHelper.runOnEDT`. > This is common practice employed inside `SwingNodeHelper.runOnEDT` to check > for lwFrame to be not null This pull request has now been integrated. Changeset: c9b74a80 Author: Prasanta Sadhukhan <[email protected]> URL: https://git.openjdk.org/jfx/commit/c9b74a80e76c03b0a3df698e6ba5c1ea239b32ad Stats: 104 lines in 2 files changed: 101 ins; 0 del; 3 mod 8371128: NullPointerException occurs due to double cleanup of SwingNode Reviewed-by: kcr ------------- PR: https://git.openjdk.org/jfx/pull/1960
