[lworld] RFR: 8377162: [lworld] getResourceAsStream() doesn't work in preview mode for exploded images [v2]

[David Beaumont]

On Thu, 19 Feb 2026 14:58:26 GMT, Alan Bateman <alanb at openjdk.org> wrote:

>> Changed to:
>> 
>>  * @summary Ensures the default runtime JRT file system has identical behavior
>>  *     in packaged or exploded builds.
>
> Okay, so the intention is that it tests the file system view of the run-time image with preview classes. Run it with preview features enabled and disabled, and ensure that the .class resources contain the expected class bytes. That's fine.
> 
> The directory is "jrtfs" so it's clear it's testing jrt-fs, so that will help shorten the name. It would be helpful if the test had "PreviewFeatures" in the name. I think the test summary for the two runs can just focus on testing that the resource contains the class bytes for class compiled with or without preview features. This is because there isn't any notion of "default runtime JRT file system" and the test only runs on the JDK under test (the test has no control over this).
> 
> Note that testParity (maybe rename to testClassBytes?) shouldn't need to translate IOException. 
> 
> In passing, the make files run the tests with -esa -ea by default so we usually don't need to include these in the test description

Oh blimey, how did I not think to add `-esa -ea`. Thank you for spotting.
I did rename methods in the last push and update the test description. I'll see if further rewording is worth it based on this comment thread.

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PR Review Comment: https://git.openjdk.org/valhalla/pull/2032#discussion_r2829140108