8278339: ServerSocket::isClosed may return false after accept throws

[AlanBateman]

JDK-8278270 introduces a small regression. If a ServerSocket is closed while another thread is blocked in the accept method then the other thread may observe isClosed returning false, i.e. code may catch IOException and check isClosed before the "closed" flag gets to true.

I've changed the close method to set the "closed" flag before closing the underlying impl. This is consistent with the network channels and also consistent with async close where the close completes on the thread that was blocked in accept. The change also prevents re-attempting the underlying impl in the unlikely event that it fails(an area that is completed unspecified). Overall I think this is preferable to have add synchronization to isClosed.

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Progress

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Issue

• JDK-8278339: ServerSocket::isClosed may return false after accept throws

Reviewers

• Daniel Fuchs (@dfuch - Reviewer)

Reviewing

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[mlbridge]

Webrevs

• 00: Full (b9e8fd57)

[dfuch]

LGTM. I agree, setting the flag before attempting to close the impl is a better behavior.

[openjdk]

@AlanBateman 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:

8278339: ServerSocket::isClosed may return false after accept throws

Reviewed-by: dfuchs

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At the time when this comment was updated there had been 4 new commits pushed to the master branch:

• 3536127: 8277383: VM.metaspace optionally show chunk freelist details
• 44fcee3: 8278289: Drop G1BlockOffsetTablePart::_object_can_span
• b2638e5: 8244602: Add JTREG_REPEAT_COUNT to repeat execution of a test
• 07669e3: 8275375: [REDO] JDK-8271949 dumppath in -XX:FlightRecorderOptions does not affect

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[AlanBateman]

/integrate

[openjdk]

Going to push as commit 69d8669.
Since your change was applied there have been 5 commits pushed to the master branch:

• 56ca66e: 8277863: Deprecate sun.misc.Unsafe methods that return offsets
• 3536127: 8277383: VM.metaspace optionally show chunk freelist details
• 44fcee3: 8278289: Drop G1BlockOffsetTablePart::_object_can_span
• b2638e5: 8244602: Add JTREG_REPEAT_COUNT to repeat execution of a test
• 07669e3: 8275375: [REDO] JDK-8271949 dumppath in -XX:FlightRecorderOptions does not affect

Your commit was automatically rebased without conflicts.

[openjdk]

@AlanBateman Pushed as commit 69d8669.

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