RFR: 8369129: Raster createPackedRaster methods specification clean up [v4]

[Sergey Bylokhov]

On Fri, 3 Oct 2025 19:35:21 GMT, Phil Race <prr at openjdk.org> wrote:

>> Updates the specification of Raster.createPackedRaster(..) methods and also the implementation of these to explicitly check the specified conditions rather than relying on them being passed up from some other API.
>> 
>> Also one each of the createInterleavedRaster(..) and createBandedRaster(..) methods have an update
>> 
>> createInterleavedRaster(...) to address that even if WxH does not exceed Integer.MAX_VALUE, the storage needed still might.
>> 
>> createBandedRaster(..) to address 
>> - a not explicitly specified or tested case that WxH must not overflow
>> - a not explicitly tested NPE case if bandMasks is null. This was relying on a de-reference and the actual check for it being null would have thrown the wrong exception type (AIOBE) - meaning not the one NPE actually specified and thrown.
>> There's an unfortunate oddity with this that of bankIndices is null it specifies and throws AIOBE, but I didn't think it worth changing either of these to make them consistent.
>> 
>> The existing CreateRasterExceptionTest.java is updated to verify all these assertions.
>> In almost all cases the behaviour is unchanged, it is just now properly specified and verified up front.
>> 
>> There are only 2 sub-tests which would fail on JDK 25
>> The test can also be run (and pass) there without this fix because it explicitly handles those 2 cases which are reasonable behavioral changes
>> - One for the  createInterleavedRaster() update where the unchecked case could end up causing a NegativeArraySizeException. This seems like a merited change.
>> - One for an unlikely case where if an app specified 0 app to createPackedRaster, divide by zero would happen.
>> 
>> The CSR is now ready for review https://bugs.openjdk.org/browse/JDK-8369131
>
> Phil Race has updated the pull request incrementally with one additional commit since the last revision:
> 
>   8369129

src/java.desktop/share/classes/java/awt/image/Raster.java line 310:

> 308:             throw new IllegalArgumentException("size too large to store image");
> 309:         }
> 310:         int size = (int)lsz;

Isn't it strange that in this method we reject "empty" images by requiring w and h to be greater than 0, but at the same time accept 0 as scanlineStride and pixelStride? This may result in empty image as well (size == 0), I think it will be rejected later but still should we check it here as well?

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PR Review Comment: https://git.openjdk.org/jdk/pull/27627#discussion_r2418526427