RFR: 8375580: Avoid using ArrayDeque in jdk.internal.loader.URLClassPath

[Eirik Bjørsnøs]

On Sun, 18 Jan 2026 09:57:51 GMT, Eirik Bjørsnøs <eirbjo at openjdk.org> wrote:

>> src/java.base/share/classes/jdk/internal/loader/URLClassPath.java line 490:
>> 
>>> 488:             for (int i = urls.length - 1; i >= 0; --i) {
>>> 489:                 loaderPath.addLast(urls[i]);
>>> 490:             }
>> 
>> Should we do `dfsUrls.addAll(Arrays.asList(urls).reversed())` for simplicity?
>
> Sympathizing with Alan's concern in the JBS about being extra cautious about introducing subtle behaviour changes in this change, I have tried to limit any cleanups not motivated by the change itself to the absolute minimum. Leaving iteration as-is also simplifies the analysis of performance implications.
> 
> I agree that the code you suggest expresses the intent much better though. If you feel confident reviewing it despite the stated concerns, I'm happy to apply it. I leave it to you.

> Should we do `dfsUrls.addAll(Arrays.asList(urls).reversed())` for simplicity?

I was overthinking this, suggestion applied, thanks :-)

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PR Review Comment: https://git.openjdk.org/jdk/pull/29288#discussion_r2702340003