On Mon, 16 Dec 2024 23:49:58 GMT, Harshitha Onkar <[email protected]> wrote:
> Win32ShellFolder2.getSystemIcon() can result in NPE if icon is null. Sanity
> null checks have been added.
>
>
> long hIcon = getSystemIcon(iconType.getIconID()); //Can return null
> Image icon = makeIcon(hIcon); // returns null if the condition (hIcon != 0L
> && hIcon != -1L) is false
> if (LARGE_ICON_SIZE != icon.getWidth(null)) { // NullPointerException -- icon
> is null
>
>
> Occurs when Windows is unable to provide a system icon and the code assumes
> an icon will **always** be returned, but the Windows API makes no such
> guarantee.
>
> getSystemIcon calls LoadIcon (User32.dll). This can return null.
> https://learn.microsoft.com/en-us/windows/win32/api/winuser/nf-winuser-loadicona
I wonder in what state the problem occurs…
[JDK-8344907](https://bugs.openjdk.org/browse/JDK-8344907) states the problem
occurs *often*.
I've never seen
[`LoadIcon`](https://learn.microsoft.com/en-us/windows/win32/api/winuser/nf-winuser-loadiconw)
fails for the standard icons. The only reason I can think of is when GDI
handles are exhausted.
-------------
Changes requested by aivanov (Reviewer).
PR Review: https://git.openjdk.org/jdk/pull/22776#pullrequestreview-2509014924
