RFR: 8345343: Hide java.lang.classfile.components package to implementation

[Adam Sotona]

On Mon, 2 Dec 2024 23:55:00 GMT, Chen Liang <liach at openjdk.org> wrote:

> The java.lang.classfile.components package was underused and had almost no usage feedback; as a result, it did not caught attention during the preview process of the Class-File API, until the late adoption when Class-File API is sure to become finalized.
> 
> To compensate in such a short time to the stabilization of JDK 24, we propose to temporarily move this package to jdk.internal instead. This allows us to better consider the role of this package and its members.
> 
> See https://mail.openjdk.org/pipermail/classfile-api-dev/2024-November/000611.html for initial problem discovery and https://mail.openjdk.org/pipermail/classfile-api-dev/2024-December/000613.html for revision proposal.

`java.lang.classfile.components.ClassPrinter` received significant positive feedback in the recent years, it became an essential debugging and logging tool.
`java.lang.classfile.components.ClassRemapper` has been designed based on user requests, it received positive feedback in the recent years and it is an essential component for class instrumentation.
`java.lang.classfile.components.CodeLocalsShifter` and `java.lang.classfile.components.CodeRelabeler` are essential components for class instrumentation and other advanced transformations, they have been designed based on the feedback from JFR class instrumentation conversion from ASM to Class-File API.
`java.lang.classfile.components.CodeStackTracker` has been designed as standalone component (out of the core Class-File API) for performance reasons. It has been strongly requested by users and it has been applied in a prototype of javac using Class-File API to generate classes.

There is no real justification for this change and I suggest to close it.

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PR Comment: https://git.openjdk.org/jdk/pull/22503#issuecomment-2514149797