On Mon, 1 Aug 2022 06:17:33 GMT, Tejesh R <t...@openjdk.org> wrote:
>> src/java.desktop/share/classes/javax/swing/DebugGraphics.java line 87:
>>
>>> 85: // directly.
>>> 86: StackWalker walker =
>>> StackWalker.getInstance(StackWalker.Option.RETAIN_CLASS_REFERENCE);
>>> 87: if ((graphics == null) && (walker.getCallerClass() !=
>>> this.getClass())) {
>>
>> I don't know if creating a StackWalker is expensive but I think it should be
>> done only if graphics == null
>>
>> Also the version of getInstance() being called here might throw
>> SecurityException
>> https://docs.oracle.com/en/java/javase/17/docs/api/java.base/java/lang/StackWalker.html#getInstance(java.lang.StackWalker.Option)
>>
>> So you'll need to wrap it in a doPrivileged.
>
> @prrace Then I will proceed by removing Stackwalker and create a graphics
> instance only if its `null`.
No, because that won't work, or more precisely will be a waste of work.
See
DebugGraphics(Graphics graphics) {
this(); // << no-args constructor and graphics will still be null
this.graphics = null;
}
graphics will ALWAYS be null when you come via here which is exactly why we
needed StackWalker
-------------
PR: https://git.openjdk.org/jdk/pull/9673
