8240903: Add test to check that jmod hashes are reproducible

[RealCLanger]

This backports a test which should have been added with JDK-8240734 in first place.
I had to do a few modifications to make it work in 11, extracted into the second commit. In 11, Files::mismatch is missing and jmod does not have the option --date.
I verified that the test fails without the changes of JDK-8240734 and passes now with it.

---

Progress

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Issue

• JDK-8240903: Add test to check that jmod hashes are reproducible

Reviewers

• Martin Doerr (@TheRealMDoerr - Reviewer)

Reviewing

Using git

Checkout this PR locally:
$ git fetch https://git.openjdk.java.net/jdk11u-dev pull/1115/head:pull/1115
$ git checkout pull/1115

Update a local copy of the PR:
$ git checkout pull/1115
$ git pull https://git.openjdk.java.net/jdk11u-dev pull/1115/head

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Checkout this PR locally:
$ git pr checkout 1115

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Using diff file

Download this PR as a diff file:
https://git.openjdk.java.net/jdk11u-dev/pull/1115.diff

[bridgekeeper]

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[mlbridge]

Webrevs

• 00: Full (88c6318c)

[openjdk]

This backport pull request has now been updated with issue from the original commit.

[TheRealMDoerr]

Modifications LGTM.

[openjdk]

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

After integration, the commit message for the final commit will be:

8240903: Add test to check that jmod hashes are reproducible

Reviewed-by: mdoerr

You can use pull request commands such as /summary, /contributor and /issue to adjust it as needed.

At the time when this comment was updated there had been 2 new commits pushed to the master branch:

• 370730f: 8181571: printing to CUPS fails on mac sandbox app
• 6faebb1: 8282422: JTable.print() failed with UnsupportedCharsetException on AIX ko_KR locale

Please see this link for an up-to-date comparison between the source branch of this pull request and the master branch.
As there are no conflicts, your changes will automatically be rebased on top of these commits when integrating. If you prefer to avoid this automatic rebasing, please check the documentation for the /integrate command for further details.

➡️ To integrate this PR with the above commit message to the master branch, type /integrate in a new comment.

[RealCLanger]

Windows GHA unrelated, will be fixed via openjdk/jdk11u#39

[RealCLanger]

/integrate

[openjdk]

Going to push as commit b3c0cc9.
Since your change was applied there have been 10 commits pushed to the master branch:

• a2e6494: 8214427: probable bug in logic of ConcurrentHashMap.addCount()
• e7036ec: 8283017: GHA: Workflows break with update release versions
• 866f8f5: 8287202: GHA: Add macOS aarch64 to the list of default platforms for workflow_dispatch event
• 25ac222: 8287017: Bump update version for OpenJDK: jdk-11.0.17
• 1c93a6e: 8285720: test/jdk/java/nio/file/Files/probeContentType/Basic.java fails to compile after backport of 8273655
• 7b58ca2: 8284094: Memory leak in invoker_completeInvokeRequest()
• 27d4c1e: 8287362: FieldAccessWatch testcase failed on AIX platform
• de59d51: 8285397: JNI exception pending in CUPSfuncs.c:250
• 370730f: 8181571: printing to CUPS fails on mac sandbox app
• 6faebb1: 8282422: JTable.print() failed with UnsupportedCharsetException on AIX ko_KR locale

Your commit was automatically rebased without conflicts.

[openjdk]

@RealCLanger Pushed as commit b3c0cc9.

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