RFR: 8372047: ClassTransform.transformingMethodBodies andThen composes incorrectly [v2]

[Adam Sotona]

On Tue, 18 Nov 2025 16:39:32 GMT, Chen Liang <liach at openjdk.org> wrote:

>> ClassMethodTransform and ClassFieldTransform are computing the chaining condition incorrectly - the composed transform should run when any of the component wants to run instead of when all copmonents want to run, and the actual content tranforms can only compose if they apply to the same set of method or fields. So we should restrict this "optimization" to same filters.
>
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>   8372047: ClassTransform.transformingMethodBodies andThen composes incorrectly

src/java.base/share/classes/jdk/internal/classfile/impl/TransformImpl.java line 123:

> 121:         @Override
> 122:         public ClassTransform andThen(ClassTransform next) {
> 123:             if (next instanceof ClassMethodTransform(var nextTransform, var nextFilter) && filter == nextFilter)

I'm trying to figure out a case where filters of the chained transforms are identical.
Is it covered by some tests?
Unless there is a real benefit in a frequent use case I suggest to remove this optimization.

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PR Review Comment: https://git.openjdk.org/jdk/pull/28377#discussion_r2540884396