8285745: Re-examine PushbackInputStream mark/reset

[bplb]

Please review this request to remove the synchronized keyword from the mark(int) and reset() methods of java.io.PushbackInputStream.

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Progress

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• Commit message must refer to an issue
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Issues

• JDK-8285745: Re-examine PushbackInputStream mark/reset
• JDK-8285759: Re-examine PushbackInputStream mark/reset (CSR)

Reviewers

• Jaikiran Pai (@jaikiran - Committer)
• Alan Bateman (@AlanBateman - Reviewer)

Reviewing

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Update a local copy of the PR:
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$ git pull https://git.openjdk.java.net/jdk pull/8433/head

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https://git.openjdk.java.net/jdk/pull/8433.diff

[bplb]

Please see also #8309.

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[openjdk]

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[mlbridge]

Webrevs

• 00: Full (c1c5187c)

[jaikiran]

Looks fine to me.
Given that mark() currently is a no-op and reset() throws an exception, the synchronized wouldn't be doing anything when it comes to calls on an exact instance of PushbackInputStream.
Calls on subclasses of PushbackInputStream which did support mark/reset, would be overriding this method already and handling any synchronization themselves.

[openjdk]

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

ℹ️ This project also has non-automated pre-integration requirements. Please see the file CONTRIBUTING.md for details.

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

8285745: Re-examine PushbackInputStream mark/reset

Reviewed-by: jpai, alanb

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 60 new commits pushed to the master branch:

• 41de506: 8285507: revert fix for JDK-8282704 now that JDK-8282952 is fixed
• 7a95a40: 8285970: gc/arguments/TestUseCompressedOopsFlagsWithUlimit.java still fails after JDK-8285011
• 4a79270: 8284632: runtime/Thread/StopAtExit.java possibly leaking memory again
• cfcba1f: 8285827: Describe the keystore.pkcs12.legacy system property in the java.security file
• 7020595: 8284435: Add dedicated filler objects for known dead Java heap areas
• 1f9f873: 8285980: Several tests in compiler/c2/irTests miss @requires vm.compiler2.enabled
• cf81f6c: 8285712: LogMessageBuffer doesn't check vsnprintf return value
• 9795ef5: 8285851: Cleanup C2AtomicParseAccess::needs_pinning()
• 3eb661b: 8285890: Fix some @param tags
• d9541c5: 8276202: LogFileOutput.invalid_file_vm asserts when being executed from a read only working directory
• ... and 50 more: https://git.openjdk.java.net/jdk/compare/1f868f1d091602cc462ee0fe5fa613a3638a5f1c...master

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.

[bplb]

/integrate

[openjdk]

Going to push as commit 9d8c3bf.
Since your change was applied there have been 60 commits pushed to the master branch:

• 41de506: 8285507: revert fix for JDK-8282704 now that JDK-8282952 is fixed
• 7a95a40: 8285970: gc/arguments/TestUseCompressedOopsFlagsWithUlimit.java still fails after JDK-8285011
• 4a79270: 8284632: runtime/Thread/StopAtExit.java possibly leaking memory again
• cfcba1f: 8285827: Describe the keystore.pkcs12.legacy system property in the java.security file
• 7020595: 8284435: Add dedicated filler objects for known dead Java heap areas
• 1f9f873: 8285980: Several tests in compiler/c2/irTests miss @requires vm.compiler2.enabled
• cf81f6c: 8285712: LogMessageBuffer doesn't check vsnprintf return value
• 9795ef5: 8285851: Cleanup C2AtomicParseAccess::needs_pinning()
• 3eb661b: 8285890: Fix some @param tags
• d9541c5: 8276202: LogFileOutput.invalid_file_vm asserts when being executed from a read only working directory
• ... and 50 more: https://git.openjdk.java.net/jdk/compare/1f868f1d091602cc462ee0fe5fa613a3638a5f1c...master

Your commit was automatically rebased without conflicts.

[openjdk]

@bplb Pushed as commit 9d8c3bf.

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