RFR: JDK-8344907 : NullPointerException in Win32ShellFolder2.getSystemIcon when "icon" is null

[Harshitha Onkar]

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

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Commit messages:
 - null check for Win icons

Changes: https://git.openjdk.org/jdk/pull/22776/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=22776&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8344907
  Stats: 2 lines in 1 file changed: 0 ins; 0 del; 2 mod
  Patch: https://git.openjdk.org/jdk/pull/22776.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/22776/head:pull/22776

PR: https://git.openjdk.org/jdk/pull/22776