RFR: 8364135: JPEGImageReader.getImageTypes() should throw exception for negative image index [v2]

[Jayathirth D V]

On Tue, 29 Jul 2025 17:22:09 GMT, Phil Race <prr at openjdk.org> wrote:

>> Jayathirth D V has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev excludes the unrelated changes brought in by the merge/rebase. The pull request contains five additional commits since the last revision:
>> 
>>  - Update test to handle all regression cases
>>  - Add checks at other places also
>>  - Merge remote-tracking branch 'upstream/master' into jpeg_getImageTypes
>>  - Check only for negative index
>>  - 8364135: JPEGImageReader.getImageTypes() should throw exception for non-zero image index
>
> src/java.desktop/share/classes/com/sun/imageio/plugins/jpeg/JPEGImageReader.java line 907:
> 
>> 905:         if (imageIndex != 0) {
>> 906:             throw new IndexOutOfBoundsException("imageIndex != 0!");
>> 907:         }
> 
> There are JPEG streams with > 1.
> And elsewhere we handle it. Look at hasNextImage()
> 
> Is this method the sole place where -1 would not throw the right exception ?

Thanks for the inputs.

getWidth(), getHeight(), getRawImageType() also need similar check.
What i have noticed is for all negative indices apart from "-1" we end up in gotoImage() function and it throws appropriate exception. Only getWidth(), getHeight(), getRawImageType() & getImageTypes() we don't throw proper exception according to spec when "-1" index is used. Also in case of getRawImageType() we actually throw NPE when "-1" index is passed.

So i have updated the code to add additional check for negative index at these places also.

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PR Review Comment: https://git.openjdk.org/jdk/pull/26522#discussion_r2289860006