8231454: File lock in Windows on a loaded jar due to a leak in Introspector::getBeanInfo

[mrserb]

java.beans.Introspector is using a new cache mechanism since Java9 in com.sun.beans.introspect.ClassInfo::CACHE which uses a SoftReference cache over the class, which makes the class "leak", unless clearing the cache manually or collecting the SoftReference by the GC.

Note that this is not a pure "leak", because the SoftReference will be collected if there is no enough memory on the system, but if the heap is big enough then all objects referenced from the cached class will be in the memory.

The class has a reference to the ClassLoader, and If the soft reference to the class is not collected by the GC, then the ClassLoader cannot be unloaded and this block the jar file removing.

The solution is to update the implementation of Introspector.flushCaches()/flushFromCaches(Class) to clear the whole cache or the cache for the specific class.

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Progress

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Testing

	Linux x64	Windows x64	macOS x64
Build	✔️ (5/5 passed)	✔️ (2/2 passed)	✔️ (2/2 passed)
Test (tier1)	✔️ (9/9 passed)	✔️ (9/9 passed)	✔️ (9/9 passed)

Issue

• JDK-8231454: File lock in Windows on a loaded jar due to a leak in Introspector::getBeanInfo

Reviewers

• Alexander Zuev (@azuev-java - Reviewer)

Download

$ git fetch https://git.openjdk.java.net/jdk pull/647/head:pull/647
$ git checkout pull/647

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[mlbridge]

Webrevs

• 00: Full (c65deec)

[azuev-java]

Looks good.

[openjdk]

@mrserb 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:

8231454: File lock in Windows on a loaded jar due to a leak in Introspector::getBeanInfo

Reviewed-by: kizune

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 129 new commits pushed to the master branch:

• acacae5: 8254843: Exception launching app on windows in some cases
• 856037c: 8255006: Add NULL-check to StringDedupTable lookup
• ee6eb98: 8254995: [x86] ControlWord::print(), rc/pc variables might not be initialized
• e577c8c: 8253641: Missing newline in the printout of certain JFR events
• 89e5444: 8254788: Dead code in the sun.java2d.xr.XRPMBlitLoops$XrSwToPMBlit
• 3267b09: 8254883: ZGC: Make the ZArrayIterator reusable for ZRelocationSetIterators
• cb6167b: 8254557: Compiler crashes with java.lang.AssertionError: isSubtype UNKNOWN
• 40f847e: 8227745: Enable Escape Analysis for Better Performance in the Presence of JVMTI Agents
• f167a71: 8254264: Remove redundant cross_modify_fence()
• 44f9271: 8254974: Fix stutter typo in TypeElement
• ... and 119 more: https://git.openjdk.java.net/jdk/compare/d7128e7daceca8b3717f3a3cd2f7a6ddba6f215d...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.

[mrserb]

/integrate

[openjdk]

@mrserb Since your change was applied there have been 154 commits pushed to the master branch:

• 42a6ead: 8254884: Make sure jvm does not crash with Arm SVE and Vector API
• e5870cf: 8252133: The java/awt/GraphicsDevice/DisplayModes/CycleDMImage.java fails if metal pipeline is active
• afc967f: 8254783: jpackage fails on Windows when application name differs from installer name
• 3ccf487: 8253019: Enhanced JPEG decoding
• cfb02d4: 8250861: Crash in MinINode::Ideal(PhaseGVN*, bool)
• 0d35235: 8249927: Specify limits of jdk.serialProxyInterfaceLimit
• d6cef99: 8245417: Improve certificate chain handling
• 24f7f84: 8245412: Better class definitions
• 00a5af4: 8248574: Improve jpeg processing
• 036da99: 8236862: Enhance support of Proxy class
• ... and 144 more: https://git.openjdk.java.net/jdk/compare/d7128e7daceca8b3717f3a3cd2f7a6ddba6f215d...master

Your commit was automatically rebased without conflicts.

Pushed as commit 2ee2b4a.

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