RFR: 8354675: Create separate image builder for hermetic [v4]

[Jiangli Zhou]

On Tue, 15 Apr 2025 14:55:57 GMT, Severin Gehwolf <sgehwolf at openjdk.org> wrote:

>> This is a start of a simple refactoring for moving hermetic handling into dedicated implementation classes. In this case I cover `ImageBuilder` and `ExecutableImage`. A similar change should be done for `ImageFileCreator` but that's for another PR.
>> 
>> @jianglizhou Please take a look. Thanks!
>> 
>> While at it I've observed the following:
>> 
>> 1. `<hermetic-image-file> --list-modules` doesn't seem to work. Shows [1] for me.
>> 2. `strip -g <hermetic-image-file>` will destroy the image. Looks like [2]. Probably a drawback for tucking on the offset after the modules file? We might want to consider building in debuginfo handling into `jlink` itself. Like the `--strip-native-debug-symbols` plugin does (but doesn't work for hermetic, yet).
>> 
>> Thoughts?
>> 
>> [1]
>> 
>> $ ./demo-image -m mod.example/com.example.demo.Main
>> [0.017s][warning][cds] Failed to open shared archive file (Not a directory)
>> Hi
>> $
>> ./demo-image --list-modules
>> [0.020s][warning][cds] Failed to open shared archive file (Not a directory)
>> Exception in thread "main" java.lang.InternalError: Unable to detect the run-time image
>> 	at java.base/jdk.internal.module.SystemModuleFinders.ofSystem(Unknown Source)
>> 	at java.base/java.lang.module.ModuleFinder.ofSystem(Unknown Source)
>> 	at java.base/jdk.internal.module.ModuleBootstrap.unlimitedFinder(Unknown Source)
>> 	at java.base/jdk.internal.module.ModuleBootstrap.limitedFinder(Unknown Source)
>> 	at java.base/sun.launcher.LauncherHelper.listModules(Unknown Source)
>> 
>> 
>> [2] This is a build with `--with-native-debug-symbols=internal` (fastdebug)
>> 
>> $ ll -lh ./demo-image 
>> -rwxr-xr-x. 1 sgehwolf sgehwolf 909M Apr 10 17:36 ./demo-image
>> $ strip -g ./demo-image 
>> $ ll -lh ./demo-image 
>> -rwxr-xr-x. 1 sgehwolf sgehwolf 50M Apr 10 18:07 ./demo-image
>> $ ./demo-image -m mod.example/com.example.demo.Main
>> Error occurred during initialization of VM
>> Failed setting boot class path.
>
> Severin Gehwolf has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Review comment v2

Looks good, thanks.

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Marked as reviewed by jiangli (Reviewer).

PR Review: https://git.openjdk.org/leyden/pull/55#pullrequestreview-2769038655