8315130: java.lang.IllegalAccessError when processing classlist to create CDS archive

[TimPushkin]

If a base class is package-private then its subclasses should have the same package name and defining class loader, otherwise IllegalAccessError is thrown when linking a subclass. Currently when dumping a static archive separate URLClassLoaders are used for each unregistered classes' source. Thus if two unregistered classes, a package-private base class and a sub class, from the same package reside in different sources IllegalAccessError will be thrown when linking the sub class. This can be unexpected because the app could have used a single class loader for both classes and thus not have seen the error — see DifferentSourcesApp.java from this patch for an example of such app.

This patch fixes the issue by using a single class loader for all unregistered classes. CDS does not allow classes with the same name making such solution possible.

---

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Issue

• JDK-8315130: java.lang.IllegalAccessError when processing classlist to create CDS archive (Bug - P4)

Reviewers

• Ioi Lam (@iklam - Reviewer)
• Calvin Cheung (@calvinccheung - Reviewer)

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[openjdk]

@TimPushkin This change now passes all automated pre-integration checks.

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8315130: java.lang.IllegalAccessError when processing classlist to create CDS archive

Reviewed-by: iklam, ccheung

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At the time when this comment was updated there had been 515 new commits pushed to the master branch:

• 5cb2317: 8351568: Improve source code documentation for PhaseCFG::insert_anti_dependences
• 1d36f17: 8351232: NPE: Cannot invoke "getDeclarationAttributes" because "sym" is null
• 883e52a: 8353237: [AArch64] Incorrect result of VectorizedHashCode intrinsic on Cortex-A53
• ... and 512 more: https://git.openjdk.org/jdk/compare/465c8e658356f658ee04397936f555f6bdffc3c2...master

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[iklam]

Hi Timofei, thanks for fixing this.

(Sorry I didn't notice this PR until now ...)

I have a suggestion for further simplification.

[iklam]

/reviewers 2

[openjdk]

@iklam
The total number of required reviews for this PR (including the jcheck configuration and the last /reviewers command) is now set to 2 (with at least 1 Reviewer, 1 Author).

[calvinccheung]

I have one comment in CDS.java.

[openjdk]

@TimPushkin this pull request can not be integrated into master due to one or more merge conflicts. To resolve these merge conflicts and update this pull request you can run the following commands in the local repository for your personal fork:

git checkout one-loader
git fetch https://git.openjdk.org/jdk.git master
git merge FETCH_HEAD
# resolve conflicts and follow the instructions given by git merge
git commit -m "Merge master"
git push

[TimPushkin]

Besides adding the warnings I noticed that UnregisteredClassLoader is omitted from the dump and implemented the same for UnregisteredClassLoader$Source and its implementations.

[calvinccheung]

Found an issue on the RegUnregSuperTest.java.

[iklam]

Looks good to me overall. I just have a request for cleaning up ClassListParser::check_supertype_overshadowing()

[TimPushkin]

Sorry, had to pause working on this for some time because of other stuff.

I believe I have addressed all the existing comments now.

[iklam]

LGTM.

[iklam]

Sorry, had to pause working on this for some time because of other stuff.

I believe I have addressed all the existing comments now.

Thanks for making the changes. Once this PR has 2 reviews and is final, I will run some tests in our test pipeline.

[calvinccheung]

Looks good. Thanks!

[TimPushkin]

Thank you!

Once this PR has 2 reviews and is final, I will run some tests in our test pipeline.

@iklam It is final, please run the tests.

[TimPushkin]

/integrate

[openjdk]

@TimPushkin
Your change (at version a3b7dd9) is now ready to be sponsored by a Committer.

[iklam]

I have merged your PR with the latest repo and running tiers 1-4 in our CI. Waiting for the results now.

[iklam]

Tests passed.
Thank you @TimPushkin for contributing this fix to OpenJDK!
/sponsor

[openjdk]

Going to push as commit 46a12e7.
Since your change was applied there have been 535 commits pushed to the master branch:

• bca293d: 8336470: Source launcher should work with service loader SPI in unnamed module
• 079fccf: 8353888: Implement JEP 510: Key Derivation Function API
• 0d86757: 8355488: Add stress mode for C2 loop peeling
• ... and 532 more: https://git.openjdk.org/jdk/compare/465c8e658356f658ee04397936f555f6bdffc3c2...master

Your commit was automatically rebased without conflicts.

[openjdk]

@iklam @TimPushkin Pushed as commit 46a12e7.

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