8288854: getLocalGraphicsEnvironment() on for multi-screen setups throws exception NPE

[mrserb]

This is the fix for a copy-paste error. The fix JDK-8076313 replaced the usage of the "screens" array from the parent class to the "devices" where the list of devices is now maintained. Since "screens" array is never used nor initialized its usage caused an NPE. That check was copied as-is, while it should use the actual number of screen devices requested early in that method.

The bug is rarely reproduced because in single screen configuration the main screen is usually 0, and in the multiscreen configuration Xinerama is usually active so the main screen is also 0 => the second part of the "if" statement is not executed.

I have validated the fix by the SwingSet, I also executed desktop tests in that config and found that even though this particular bug is fixed we still have many issues there, around ~100 tests failed.

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Issue

• JDK-8288854: getLocalGraphicsEnvironment() on for multi-screen setups throws exception NPE

Reviewers

• Alexander Zvegintsev (@azvegint - Reviewer)
• Alexey Ivanov (@aivanov-jdk - Reviewer)

Reviewing

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[bridgekeeper]

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[openjdk]

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[mlbridge]

Webrevs

• 00: Full (f46785b8)

[azvegint]

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:

8288854: getLocalGraphicsEnvironment() on for multi-screen setups throws exception NPE

Reviewed-by: azvegint, aivanov

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 10 new commits pushed to the master branch:

• dbc6e11: 8289399: Update SourceVersion to use snippets
• 1504804: 8289398: ProblemList jdk/jfr/api/consumer/recordingstream/TestOnEvent.java on linux-x64 again
• 9b7805e: 8289069: Very slow C1 arraycopy jcstress tests after JDK-8279886
• c42b796: 8288058: Broken links on constant-values page
• a814293: 8275784: Bogus warning generated for record with compact constructor
• 6f9717b: 8288836: (fs) Files.writeString spec for IOException has "specified charset" when no charset is provided
• 9048cef: 8288425: Footprint regression due MH creation when initializing StringConcatFactory
• adbd200: 8289228: SegmentAllocator::allocateArray null handling is too lax
• b449038: 8288445: AArch64: C2 compilation fails with guarantee(!true || (true && (shift != 0))) failed: impossible encoding
• 2efa89a: 8289251: ProblemList java/lang/ref/OOMEInReferenceHandler.java

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.

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[azvegint]

BTW why this PR is raised against JDK19 and not mainline?

[mrserb]

BTW why this PR is raised against JDK19 and not mainline?

Don't all fixes from JDK19 have merged to the mainline "automatically"?

[azvegint]

BTW why this PR is raised against JDK19 and not mainline?

Don't all fixes from JDK19 have merged to the mainline "automatically"?

I worried that JDK19 are in RDP1 phase right now.

This bug looks like a "Targeted P3" and it should be dropped.

Correct me if I am wrong.

[mrserb]

Don't all fixes from JDK19 have merged to the mainline "automatically"?

I worried that JDK19 are in RDP1 phase right now.

This is the phase when all fixes are merged to the mainline.

From your links above:
" In RDP 1, if the bug is targeted and if time permits, develop and integrate a fix when ready."

	Fix	Drop
RDP1	Current P1–P3	All P4–P5
	Targeted P1–P3 if time	Targeted P1–P3
	P1–P5 doc/test bugs

Since the small fix for a recent regression is ready I do not see a reason to skip it?

[azvegint]

Since the small fix for a recent regression is ready I do not see a reason to skip it?

OK, thanks for clarification.

[mrserb]

/integrate

[openjdk]

Going to push as commit cfc9a88.
Since your change was applied there have been 18 commits pushed to the master branch:

• 9925014: 8280320: C2: Loop opts are missing during OSR compilation
• 8e01ffb: 8289570: SegmentAllocator:allocateUtf8String(String str) default behavior mismatch to spec
• 20124ac: 8289585: ProblemList sun/tools/jhsdb/JStackStressTest.java on linux-aarch64
• 604ea90: 8289549: ISO 4217 Amendment 172 Update
• 9549777: 8284358: Unreachable loop is not removed from C2 IR, leading to a broken graph
• c20b3aa: 8289278: Suspend/ResumeAllVirtualThreads need both can_suspend and can_support_virtual_threads
• cf71544: 8289252: Recommend Locale.of() method instead of the constructor
• 5708974: 8288596: Random:from() adapter does not delegate to supplied generator in all cases
• dbc6e11: 8289399: Update SourceVersion to use snippets
• 1504804: 8289398: ProblemList jdk/jfr/api/consumer/recordingstream/TestOnEvent.java on linux-x64 again
• ... and 8 more: https://git.openjdk.org/jdk19/compare/17ef8cae33dd77e5a9b2cf19539ebf25aece5f92...master

Your commit was automatically rebased without conflicts.

[openjdk]

@mrserb Pushed as commit cfc9a88.

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